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Rohr J, Vahidy FS, Bartek N, Bourassa KA, Nanavaty NR, Antosh DD, Harms KP, Stanley JL, Madan A. Reducing psychiatric illness in the perinatal period: A review and commentary. World J Psychiatry 2023; 13:149-160. [PMID: 37123098 PMCID: PMC10130961 DOI: 10.5498/wjp.v13.i4.149] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/16/2022] [Revised: 02/08/2023] [Accepted: 03/31/2023] [Indexed: 04/18/2023] Open
Abstract
This brief overview highlights the global crisis of perinatal psychiatric illness (PPI). PPI is a major contributor to many adverse pregnancy, childbirth, and childhood development outcomes. It contributes to billions of dollars in spending worldwide each year and has a significant impact on the individual, their family, and their community. It is also highly preventable. Current recommendations for intervention and management of PPI are limited and vary considerably from country to country. Furthermore, there are several significant challenges asso-ciated with implementation of these recommendations. These challenges are magnified in number and consequence among women of color and/or minority populations, who experience persistent and negative health disparities during pregnancy and the postpartum period. This paper aims to provide a broad overview of the current state of recommendations and implementation challenges for PPI and layout a framework for overcoming these challenges. An equity-informed model of care that provides universal intervention for pregnant women may be one solution to address the preventable consequences of PPI on child and maternal health. Uniquely, this model emphasizes the importance of managing and eliminating known barriers to traditional health care models. Culturally and contextually specific challenges must be overcome to fully realize the impact of improved management of PPI.
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Affiliation(s)
- Jessica Rohr
- Department of Psychiatry and Behavioral Health, Houston Methodist, Houston, TX 77030, United States
| | - Farhaan S Vahidy
- Department of Neurosurgery, Houston Methodist, Houston, TX 77030, United States
| | - Nicole Bartek
- Department of Psychiatry and Behavioral Health, Houston Methodist, Houston, TX 77030, United States
| | - Katelynn A Bourassa
- Department of Psychiatry and Behavioral Health, Houston Methodist, Houston, TX 77030, United States
| | - Namrata R Nanavaty
- Department of Psychiatry and Behavioral Health, Houston Methodist, Houston, TX 77030, United States
| | - Danielle D Antosh
- Department of Obstetrics and Gynecology, Houston Methodist, Houston, TX 77030, United States
| | - Konrad P Harms
- Department of Obstetrics and Gynecology, Houston Methodist, Houston, TX 77030, United States
| | - Jennifer L Stanley
- Department of Obstetrics and Gynecology, Houston Methodist, Houston, TX 77030, United States
| | - Alok Madan
- Department of Psychiatry and Behavioral Health, Houston Methodist, Houston, TX 77030, United States
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Daversa DR, Hechinger RF, Madin E, Fenton A, Dell AI, Ritchie EG, Rohr J, Rudolf VHW, Lafferty KD. Broadening the ecology of fear: non-lethal effects arise from diverse responses to predation and parasitism. Proc Biol Sci 2021; 288:20202966. [PMID: 33622122 DOI: 10.1098/rspb.2020.2966] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023] Open
Abstract
Research on the 'ecology of fear' posits that defensive prey responses to avoid predation can cause non-lethal effects across ecological scales. Parasites also elicit defensive responses in hosts with associated non-lethal effects, which raises the longstanding, yet unresolved question of how non-lethal effects of parasites compare with those of predators. We developed a framework for systematically answering this question for all types of predator-prey and host-parasite systems. Our framework reveals likely differences in non-lethal effects not only between predators and parasites, but also between different types of predators and parasites. Trait responses should be strongest towards predators, parasitoids and parasitic castrators, but more numerous and perhaps more frequent for parasites than for predators. In a case study of larval amphibians, whose trait responses to both predators and parasites have been relatively well studied, existing data indicate that individuals generally respond more strongly and proactively to short-term predation risks than to parasitism. Apart from studies using amphibians, there have been few direct comparisons of responses to predation and parasitism, and none have incorporated responses to micropredators, parasitoids or parasitic castrators, or examined their long-term consequences. Addressing these and other data gaps highlighted by our framework can advance the field towards understanding how non-lethal effects impact prey/host population dynamics and shape food webs that contain multiple predator and parasite species.
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Affiliation(s)
- D R Daversa
- La Kretz Center for California Conservation Science, Institute for the Environment and Sustainability, University of California, Los Angeles, CA, USA.,Institute of Integrative Biology, University of Liverpool, Liverpool, UK.,National Great Rivers Research and Education Centre (NGRREC), East Alton, IL 62024, USA
| | - R F Hechinger
- Scripps Institution of Oceanography, University of California, San Diego, San Diego, CA, USA
| | - E Madin
- Hawai'i Institute of Marine Biology, University of Hawai'i, Kane'ohe, HI 96744, USA
| | - A Fenton
- Institute of Integrative Biology, University of Liverpool, Liverpool, UK
| | - A I Dell
- National Great Rivers Research and Education Centre (NGRREC), East Alton, IL 62024, USA.,Department of Biology, Washington University of St Louis, St Louis, MO 63130, USA.,Department of Biology, Saint Louis University, Saint Louis, MO 63130, USA
| | - E G Ritchie
- School of Life and Environmental Sciences, Centre for Integrative Ecology (Burwood Campus), Deakin University, Geelong, Victoria 3220, Australia
| | - J Rohr
- Department of Biological Sciences, University of Notre Dame, Notre Dame, IN, USA
| | | | - K D Lafferty
- Western Ecological Research Center, US Geological Survey, at UC Santa Barbara, Santa Barbara, CA, USA
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3
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Rohr J, Guo S, Huo J, Bouska A, Lachel C, Li Y, Simone PD, Zhang W, Gong Q, Wang C, Cannon A, Heavican T, Mottok A, Hung S, Rosenwald A, Gascoyne R, Fu K, Greiner TC, Weisenburger DD, Vose JM, Staudt LM, Xiao W, Borgstahl GEO, Davis S, Steidl C, McKeithan T, Iqbal J, Chan WC. Recurrent activating mutations of CD28 in peripheral T-cell lymphomas. Leukemia 2015; 30:1062-70. [PMID: 26719098 DOI: 10.1038/leu.2015.357] [Citation(s) in RCA: 90] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2015] [Revised: 10/30/2015] [Accepted: 12/15/2015] [Indexed: 11/09/2022]
Abstract
Peripheral T-cell lymphomas (PTCLs) comprise a heterogeneous group of mature T-cell neoplasms with a poor prognosis. Recently, mutations in TET2 and other epigenetic modifiers as well as RHOA have been identified in these diseases, particularly in angioimmunoblastic T-cell lymphoma (AITL). CD28 is the major co-stimulatory receptor in T cells which, upon binding ligand, induces sustained T-cell proliferation and cytokine production when combined with T-cell receptor stimulation. We have identified recurrent mutations in CD28 in PTCLs. Two residues-D124 and T195-were recurrently mutated in 11.3% of cases of AITL and in one case of PTCL, not otherwise specified (PTCL-NOS). Surface plasmon resonance analysis of mutations at these residues with predicted differential partner interactions showed increased affinity for ligand CD86 (residue D124) and increased affinity for intracellular adaptor proteins GRB2 and GADS/GRAP2 (residue T195). Molecular modeling studies on each of these mutations suggested how these mutants result in increased affinities. We found increased transcription of the CD28-responsive genes CD226 and TNFA in cells expressing the T195P mutant in response to CD3 and CD86 co-stimulation and increased downstream activation of NF-κB by both D124V and T195P mutants, suggesting a potential therapeutic target in CD28-mutated PTCLs.
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Affiliation(s)
- J Rohr
- Department of Pathology and Microbiology, University of Nebraska Medical Center, Omaha, NE, USA.,Department of Pathology, City of Hope National Medical Center, Duarte, CA, USA
| | - S Guo
- Department of Pathology, Xi Jing Hospital, Fourth Military Medical University, Xi'an, Shaan Xi Province, China
| | - J Huo
- Radcliffe Department of Medicine, University of Oxford, Oxford, UK
| | - A Bouska
- Department of Pathology and Microbiology, University of Nebraska Medical Center, Omaha, NE, USA
| | - C Lachel
- Department of Pathology and Microbiology, University of Nebraska Medical Center, Omaha, NE, USA
| | - Y Li
- Department of Pathology, City of Hope National Medical Center, Duarte, CA, USA
| | - P D Simone
- Internal Medicine Residency Program, Florida Atlantic University College of Medicine, Boca Raton, FL, USA
| | - W Zhang
- Department of Pathology and Microbiology, University of Nebraska Medical Center, Omaha, NE, USA
| | - Q Gong
- Department of Pathology, City of Hope National Medical Center, Duarte, CA, USA
| | - C Wang
- Department of Pathology and Microbiology, University of Nebraska Medical Center, Omaha, NE, USA.,Department of Pathology, City of Hope National Medical Center, Duarte, CA, USA.,School of Medicine, Shandong University, Jinan, China
| | - A Cannon
- Department of Pathology and Microbiology, University of Nebraska Medical Center, Omaha, NE, USA
| | - T Heavican
- Department of Pathology and Microbiology, University of Nebraska Medical Center, Omaha, NE, USA
| | - A Mottok
- Department for Lymphoid Cancer Research, Centre for Lymphoid Cancer, BC Cancer Agency, Vancouver, BC, Canada.,Department of Pathology and Laboratory Medicine, University of British Columbia, Vancouver, BC, Canada
| | - S Hung
- Department for Lymphoid Cancer Research, Centre for Lymphoid Cancer, BC Cancer Agency, Vancouver, BC, Canada.,Department of Pathology and Laboratory Medicine, University of British Columbia, Vancouver, BC, Canada
| | - A Rosenwald
- Institute of Pathology and Comprehensive Cancer Center Mainfranken (CCC MF), University of Wuerzburg, Wuerzburg, Germany
| | - R Gascoyne
- Department for Lymphoid Cancer Research, Centre for Lymphoid Cancer, BC Cancer Agency, Vancouver, BC, Canada.,Department of Pathology and Laboratory Medicine, University of British Columbia, Vancouver, BC, Canada
| | - K Fu
- Department of Pathology and Microbiology, University of Nebraska Medical Center, Omaha, NE, USA
| | - T C Greiner
- Department of Pathology and Microbiology, University of Nebraska Medical Center, Omaha, NE, USA
| | - D D Weisenburger
- Department of Pathology, City of Hope National Medical Center, Duarte, CA, USA
| | - J M Vose
- Department of Medicine, University of Nebraska Medical Center, Omaha, NE, USA
| | - L M Staudt
- National Institutes of Health, Bethesda, MD, USA
| | - W Xiao
- Division of Bioinformatics and Biostatistics, National Center for Toxicological Research, Food and Drug Administration, Washington, DC, USA
| | - G E O Borgstahl
- Eppley Institute for Cancer Research and Allied Diseases, University of Nebraska Medical Center, Omaha, NE, USA
| | - S Davis
- Radcliffe Department of Medicine, University of Oxford, Oxford, UK
| | - C Steidl
- Department for Lymphoid Cancer Research, Centre for Lymphoid Cancer, BC Cancer Agency, Vancouver, BC, Canada.,Department of Pathology and Laboratory Medicine, University of British Columbia, Vancouver, BC, Canada
| | - T McKeithan
- Department of Pathology, City of Hope National Medical Center, Duarte, CA, USA
| | - J Iqbal
- Department of Pathology and Microbiology, University of Nebraska Medical Center, Omaha, NE, USA
| | - W C Chan
- Department of Pathology, City of Hope National Medical Center, Duarte, CA, USA
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Matselyukh B, Mohammadipanah F, Laatsch H, Rohr J, Efremenkova O, Khilya V. Purification and structure elucidation of the by-product of new regulator of antibiotic production and differentiation of Streptomyces. Mikrobiol Z 2012; 74:66-73. [PMID: 23120988] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
Streptomyces globisporus 1912, a producer of the antitumor antibiotic landomycin E, forms the new low-molecular signaling molecule N-methylphenylalanyl-dehydrobutyrine diketopiperazine (BDD) and its complex and unstable by-product which restore, like the A-factor in Streptomyces griseus 773, landomycin E and streptomycin biosynthesis, and sporulation of the defective mutants S. globisporus 1912-B2 and S. griseus 1439, respectively. Here, we report the purification and structure elucidation of two compounds with R(f)0.8 by HPLC, LC/MS and 1HMR analysis. These compounds have m/z 338 and 384, accordingly, and each of them is presented by two stereoisomers containing BDD in their structure. A hypothesis explaining the composition and regulatory properties of these unstable compounds is presented.
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Affiliation(s)
- B Matselyukh
- Zabolotny Institute of Microbiology and Virology, National Academy of Sciences of Ukraine, 154 Acad. Zabolotny St., Kyiv D 03680, Ukraine
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Ostash B, Ostash I, Zhu L, Kharel MK, Luzhetskyy A, Bechthold A, Walker S, Rohr J, Fedorenko V. Properties of lanK-based regulatory circuit involved in landomycin biosynthesis in Streptomyces cyanogenus S136. RUSS J GENET+ 2010. [DOI: 10.1134/s1022795410050030] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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Ostash B, Ostash I, Zhu L, Kharel MK, Luzhetskyy A, Bechthold A, Walker S, Rohr J, Fedorenko V. Properties of lanK-based regulatory circuit involved in landomycin biosynthesis in Streptomyces cyanogenus S136. Genetika 2010; 46:604-609. [PMID: 20583594 PMCID: PMC2905788] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
LanK is TetR-like regulatory protein recently shown to regulate the export and glycosylation of landomycins in Streptomyces cyanogenus S136. Here, several properties of the lanK-mediated regulation were deciphered. LanK seems to function as oligomer as evident from experiments in vitro. In vivo, it is able to recognize various landomycins with altered aglycon structure and the minimal concentration of landomycin A sensed by LanK lies in low nanomolar range. Coexpression studies showed that the positive regulatory gene lanI upregulates lanK-dependent lan genes once the negative LanK-regulation is cancelled. Gene lanK can be useful for the construction of biosensor strains for sensitive and specific identification of producers of landomycin-like molecules with long glycosidic chains.
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Affiliation(s)
- B. Ostash
- Department of Genetics and Biotechnology, Ivan Franko National University of L’viv, L’viv, 79005 Ukraine
| | - I. Ostash
- Department of Genetics and Biotechnology, Ivan Franko National University of L’viv, L’viv, 79005 Ukraine
- Department of Microbiology and Molecular Genetics, Harvard Medical School, Boston, MA 02115 USA
| | - L. Zhu
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Kentucky, Lexington, KY 40536-0082 USA
| | - M. K. Kharel
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Kentucky, Lexington, KY 40536-0082 USA
| | - A. Luzhetskyy
- Albert-Ludwigs-Universität Freiburg, Institut für Pharmazeutische Wissenschaften, Pharmazeutische Biologie und Biotechnologie, Freiburg, 79104 Germany
| | - A. Bechthold
- Albert-Ludwigs-Universität Freiburg, Institut für Pharmazeutische Wissenschaften, Pharmazeutische Biologie und Biotechnologie, Freiburg, 79104 Germany
| | - S. Walker
- Department of Microbiology and Molecular Genetics, Harvard Medical School, Boston, MA 02115 USA
| | - J. Rohr
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Kentucky, Lexington, KY 40536-0082 USA
| | - V. Fedorenko
- Department of Genetics and Biotechnology, Ivan Franko National University of L’viv, L’viv, 79005 Ukraine
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Speckmann C, Enders A, Woellner C, Thiel D, Rensing-Ehl A, Schlesier M, Rohr J, Jakob T, Oswald E, Kopp M, Sanal O, Litzman J, Plebani A, Pietrogrande M, Franco J, Espanol T, Grimbacher B, Ehl S. Reduced memory B cells in patients with hyper IgE syndrome. Clin Immunol 2008; 129:448-54. [DOI: 10.1016/j.clim.2008.08.002] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2008] [Revised: 07/15/2008] [Accepted: 08/09/2008] [Indexed: 10/21/2022]
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Malek A, Núñez L, Menéndez N, Morís F, Carbone G, Rohr J, Méndez C, Salas J, Catapano C. 182 POSTER In vitro and in vivo antitumor activity of novel aureolic acid analogues generated by metabolic engineering of the biosynthetic pathways in Streptomyces argillaceus and treptomyces griseus subsp. griseus. EJC Suppl 2008. [DOI: 10.1016/s1359-6349(08)72114-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
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Rohr J, Allen EG, Charen K, Giles J, He W, Dominguez C, Sherman SL. Anti-Mullerian hormone indicates early ovarian decline in fragile X mental retardation (FMR1) premutation carriers: a preliminary study. Hum Reprod 2008; 23:1220-5. [PMID: 18310677 DOI: 10.1093/humrep/den050] [Citation(s) in RCA: 72] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
BACKGROUND Women who carry the fragile X mental retardation (FMR1) premutation are at risk for fragile X-associated primary ovarian insufficiency. Past studies have shown that carriers who are still cycling have increased levels FSH compared with non-carriers. As anti-Mullerian hormone (AMH) has been shown as an excellent marker of ovarian decline, we examined AMH levels among premutation carriers to characterize their ovarian function. METHODS We determined the level of FSH and AMH in serum samples collected during early follicular phase from women who carried longer FMR1 repeat alleles (defined as >or=70 repeats, n = 40) and those with shorter repeat alleles (<70 repeats, n = 75), identified by DNA analysis. Comparisons were made stratified by age and carrier status. RESULTS For all age groups, AMH levels were significantly lower among longer repeat allele carriers compared to shorter repeat allele carriers (P = 0.002, 0.006 and 0.020 for women ages 18-30, 31-40 and 41-50 years, respectively). In contrast, increased FSH indicative of early ovarian decline was only evident for longer repeat allele carriers aged 31-40 years (P = 0.089, 0.001 and 0.261 for women ages 18-30, 31-40 and 41-50 years, respectively). CONCLUSIONS These preliminary data suggest that AMH levels indicate early ovarian decline among women with longer FMR1 repeat alleles; moreover, AMH appears to be a better marker than FSH in identifying this early decline.
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Affiliation(s)
- J Rohr
- Department of Human Genetics, Emory University School of Medicine, 615 Michael Street, Suite 301, Whitehead Building, Atlanta, GA 30322, USA
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10
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Fedoryshyn M, Nur-e-Alam M, Zhu L, Luzhetskyy A, Rohr J, Bechthold A. Surprising production of a new urdamycin derivative by S. fradiae Delta urdQ/R. J Biotechnol 2007; 130:32-8. [PMID: 17434221 PMCID: PMC2880504 DOI: 10.1016/j.jbiotec.2007.02.018] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2007] [Accepted: 02/19/2007] [Indexed: 11/30/2022]
Abstract
A strain (S. fradiae Delta urdQ/R) with mutations in urdQ and urdR encoding a dTDP-hexose-3,4-dehydratase and a dTDP-hexose-4-ketoreductase, respectively, produces a new urdamycin analogue (urdamycin X) with changes in the polyketide structure. The structure of urdamycin X has been elucidated by NMR spectroscopy. Urdamycin X was not detectable, even in small amounts, in either S. fradiae Delta urdQ, in S. fradiae DeltaurdR or in S. fradiae A0, a mutant lacking all glycosyltransferase genes. Complementation of S. fradiae Delta urdQ/R restored urdamycin A production indicating that the mutations did not cause any polar effect.
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Affiliation(s)
- M. Fedoryshyn
- Institut für Pharmazeutische Wissenschaften, Lehrstuhl für Pharmazeutische Biologie und Biotechnologie Albert-Ludwigs-Universität Freiburg, Stefan-Meier-Strasse 19, 79104 Freiburg, Germany
| | - M. Nur-e-Alam
- Pharmaceutical Sciences, College of Pharmacy, University of Kentucky, 725 Rose street, Lexington, KY 40536-0082, USA
| | - L. Zhu
- Pharmaceutical Sciences, College of Pharmacy, University of Kentucky, 725 Rose street, Lexington, KY 40536-0082, USA
| | - A. Luzhetskyy
- Institut für Pharmazeutische Wissenschaften, Lehrstuhl für Pharmazeutische Biologie und Biotechnologie Albert-Ludwigs-Universität Freiburg, Stefan-Meier-Strasse 19, 79104 Freiburg, Germany
| | - J. Rohr
- Institut für Pharmazeutische Wissenschaften, Lehrstuhl für Pharmazeutische Biologie und Biotechnologie Albert-Ludwigs-Universität Freiburg, Stefan-Meier-Strasse 19, 79104 Freiburg, Germany
- Corresponding author (chemistry). Tel.: +1 859 323 5031; fax: +1 859 257 7564
| | - A. Bechthold
- Pharmaceutical Sciences, College of Pharmacy, University of Kentucky, 725 Rose street, Lexington, KY 40536-0082, USA
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Trummer G, Rohr J, Heilmann C, Berchtold-Herz M, Sorg S, Weigang E, Beyersdorf F. Percutaneous Dilatational Tracheostomy (PDT) is a safe procedure and does not increase the risk for sternal wound infections and mediastinitis in cardiothoracic patients. Thorac Cardiovasc Surg 2007. [DOI: 10.1055/s-2007-967343] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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Albertini V, Vignati S, Rinaldi A, Bertoni F, Rohr J, Carbone G, Catapano C. 546 A novel aureolic acid antibiotic analogue has potent anti-proliferative activity and induces multiple changes in gene expression in ovarian cancer cells. EJC Suppl 2004. [DOI: 10.1016/s1359-6349(04)80554-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
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Abstract
A field measurement and computer modeling effort was made to assess the dilution field of pulped waste materials discharged into the wake of a US Navy frigate. Pulped paper and fluorescein dye were discharged from the frigate's pulper at known rates. The subsequent particle and dye concentration field was then measured throughout the wake by a following vessel using multiple independent measures. Minimum dilution of the pulped paper reached 3.2 x 10(5) within 1900 m behind the frigate, or about 8 min after discharge. Independent measures typically agreed within 25% of one another and within 20% of model predictions. Minimum dilution of dye reached 2.3 x 10(5) at a down-wake distance of approximately 3500 m, or roughly 15 min. Comparison to model measurements were again within 20%. The field test was not only successful at characterizing wake dilution under one set of at-sea conditions, but was successful at validating the computer model used for assessing a wide range of ships and conditions.
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Affiliation(s)
- C N Katz
- Space and Naval Warfare Systems Center San Diego, 53560 Hull Street, San Diego, CA 92152-5000, USA.
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14
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Trefzer A, Fischer C, Stockert S, Westrich L, Künzel E, Girreser U, Rohr J, Bechthold A. Elucidation of the function of two glycosyltransferase genes (lanGT1 and lanGT4) involved in landomycin biosynthesis and generation of new oligosaccharide antibiotics. Chem Biol 2001; 8:1239-52. [PMID: 11755402 DOI: 10.1016/s1074-5521(01)00091-6] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
BACKGROUND The genetic engineering of antibiotic-producing Streptomyces strains is an approach that became a successful methodology in developing new natural polyketide derivatives. Glycosyltransferases are important biosynthetic enzymes that link sugar moieties to aglycones, which often derive from polyketides. Biological activity is frequently generated along with this process. Here we report the use of glycosyltransferase genes isolated from the landomycin biosynthetic gene cluster to create hybrid landomycin/urdamycin oligosaccharide antibiotics. RESULTS Production of several novel urdamycin derivatives by a mutant of Streptomyces fradiae Tü2717 has been achieved in a combinatorial biosynthetic approach using glycosyltransferase genes from the landomycin producer Streptomyces cyanogenus S136. For the generation of gene cassettes useful for combinatorial biosynthesis experiments new vectors named pMUNI, pMUNII and pMUNIII were constructed. These vectors facilitate the construction of gene combinations taking advantage of the compatible MunI and EcoRI restriction sites. CONCLUSIONS The high-yielding production of novel oligosaccharide antibiotics using glycosyltransferase gene cassettes generated in a very convenient way proves that glycosyltransferases can be flexible towards the alcohol substrate. In addition, our results indicate that LanGT1 from S. cyanogenus S136 is a D-olivosyltransferase, whereas LanGT4 is a L-rhodinosyltransferase.
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Affiliation(s)
- A Trefzer
- Albert-Ludwigs-Universität Freiburg im Breisgau, Pharmazeutische Biologie, Freiburg, Germany
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15
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Patallo EP, Blanco G, Fischer C, Brana AF, Rohr J, Mendez C, Salas JA. Deoxysugar Methylation during Biosynthesis of the Antitumor Polyketide Elloramycin by Streptomyces olivaceus. J Biol Chem 2001; 276:18765-74. [PMID: 11376004 DOI: 10.1074/jbc.m101225200] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The anthracycline-like polyketide drug elloramycin is produced by Streptomyces olivaceus Tü2353. Elloramycin has antibacterial activity against Gram-positive bacteria and also exhibits antitumor activity. From a cosmid clone (cos16F4) containing part of the elloramycin biosynthesis gene cluster, three genes (elmMI, elmMII, and elmMIII) have been cloned. Sequence analysis and data base comparison showed that their deduced products resembled S-adenosylmethionine-dependent O-methyltransferases. The genes were individually expressed in Streptomyces albus and also coexpressed with genes involved in the biosynthesis of l-rhamnose, the 6-deoxysugar attached to the elloramycin aglycon. The resulting recombinant strains were used to biotransform three different elloramycin-type compounds: l-rhamnosyl-tetracenomycin C, l-olivosyl-tetracenomycin C, and l-oleandrosyl-tetracenomycin, which differ in their 2'-, 3'-, and 4'-substituents of the sugar moieties. When only the three methyltransferase-encoding genes elmMI, elmMII, and elmMIII were individually expressed in S. albus, the methylating activity of the three methyltransferases was also assayed in vitro using various externally added glycosylated substrates. From the combined results of all of these experiments, it is proposed that methyltransferases ElmMI, ElmMII, and ElmMIII are involved in the biosynthesis of the permethylated l-rhamnose moiety of elloramycin. ElmMI, ElmMII, and ElmMIII are responsible for the consecutive methylation of the hydroxy groups at the 2'-, 3'-, and 4'-position, respectively, after the sugar moiety has been attached to the aglycon.
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Affiliation(s)
- E P Patallo
- Departamento de Biologia Funcional e Instituto Universitario de Oncologia del Principado de Asturias, Universidad de Oviedo, 33006 Oviedo, Spain
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16
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Blanco G, Patallo EP, Braña AF, Trefzer A, Bechthold A, Rohr J, Méndez C, Salas JA. Identification of a sugar flexible glycosyltransferase from Streptomyces olivaceus, the producer of the antitumor polyketide elloramycin. Chem Biol 2001; 8:253-63. [PMID: 11306350 DOI: 10.1016/s1074-5521(01)00010-2] [Citation(s) in RCA: 76] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND Elloramycin is an anthracycline-like antitumor drug related to tetracenomycin C which is produced by Streptomyces olivaceus Tü2353. Structurally is a tetracyclic aromatic polyketide derived from the condensation of 10 acetate units. Its chromophoric aglycon is glycosylated with a permethylated L-rhamnose moiety at the C-8 hydroxy group. Only limited information is available about the genes involved in the biosynthesis of elloramycin. From a library of chromosomal DNA from S. olivaceus, a cosmid (16F4) was isolated that contains part of the elloramycin gene cluster and when expressed in Streptomyces lividans resulted in the production of a non-glycosylated intermediate in elloramycin biosynthesis, 8-demethyl-tetracenomycin C (8-DMTC). RESULTS The expression of cosmid 16F4 in several producers of glycosylated antibiotics has been shown to produce tetracenomycin derivatives containing different 6-deoxysugars. Different experimental approaches showed that the glycosyltransferase gene involved in these glycosylation events was located in 16F4. Using degenerated oligoprimers derived from conserved amino acid sequences in glycosyltransferases, the gene encoding this sugar flexible glycosyltransferase (elmGT) has been identified. After expression of elmGT in Streptomyces albus under the control of the erythromycin resistance promoter, ermEp, it was shown that elmG can transfer different monosaccharides (both L- and D-sugars) and a disaccharide to 8-DMTC. Formation of a diolivosyl derivative in the mithramycin producer Streptomyces argillaceus was found to require the cooperative action of two mithramycin glycosyltransferases (MtmGI and MtmGII) responsible for the formation of the diolivosyl disaccharide, which is then transferred by ElmGT to 8-DMTC. CONCLUSIONS The ElmGT glycosyltransferase from S. olivaceus Tü2353 can transfer different sugars into the aglycon 8-DMTC. In addition to its natural sugar substrate L-rhamnose, ElmGT can transfer several L- and D-sugars and also a diolivosyl disaccharide into the aglycon 8-DMTC. ElmGT is an example of sugar flexible glycosyltransferase and can represent an important tool for combinatorial biosynthesis.
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Affiliation(s)
- G Blanco
- Departamento of Biología, Functional e Instituto Universitario del Principado de Asturias, Universidad de Oviedo, Spain
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17
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González A, Remsing LL, Lombó F, Fernández MJ, Prado L, Braña AF, Künzel E, Rohr J, Méndez C, Salas JA. The mtmVUC genes of the mithramycin gene cluster in Streptomyces argillaceus are involved in the biosynthesis of the sugar moieties. Mol Gen Genet 2001; 264:827-35. [PMID: 11254130 DOI: 10.1007/s004380000372] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Mithramycin is a glycosylated aromatic polyketide produced by Streptomyces argillaceus, and is used as an antitumor drug. Three genes (mtmV, mtmU and mtmC) from the mithramycin gene cluster have been cloned, and characterized by DNA sequencing and by analysis of the products that accumulate in nonproducing mutants, which were generated by insertional inactivation of these genes. The mtm V gene codes for a 2,3-dehydratase that catalyzes early and common steps in the biosynthesis of the three sugars found in mithramycin (D-olivose, D-oliose and D-mycarose); its inactivation caused the accumulation of the nonglycosylated intermediate premithramycinone. The mtmU gene codes for a 4-ketoreductase involved in D-oliose biosynthesis, and its inactivation resulted in the accumulation of premithramycinone and premithramycin A , the first glycosylated intermediate which contains a D-olivose unit. The third gene, mtmC, is involved in D-mycarose biosynthesis and codes for a C-methyltransferase. Two mutants with lesions in the mtmC gene accumulated mithramycin intermediates lacking the D-mycarose moiety but containing D-olivose units attached to C-12a in which the 4-keto group is unreduced. This suggests that mtmC could code for a second enzyme activity, probably a D-olivose 4-ketoreductase, and that the glycosyltransferase responsible for the incorporation of D-olivose (MtmGIV) shows some degree of flexibility with respect to its sugar co-substrate, since the 4-ketoanalog is also transferred. A pathway is proposed for the biosynthesis of the three sugar moieties in mithramycin.
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Affiliation(s)
- A González
- Departamento de Biología Funcional e Instituto Universitario de Oncología del Principado de Asturias, Universidad de Oviedo, Spain
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18
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Hoffmeister D, Ichinose K, Domann S, Faust B, Trefzer A, Dräger G, Kirschning A, Fischer C, Künzel E, Bearden D, Rohr J, Bechthold A. The NDP-sugar co-substrate concentration and the enzyme expression level influence the substrate specificity of glycosyltransferases: cloning and characterization of deoxysugar biosynthetic genes of the urdamycin biosynthetic gene cluster. Chem Biol 2000; 7:821-31. [PMID: 11094336 DOI: 10.1016/s1074-5521(00)00029-6] [Citation(s) in RCA: 76] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
BACKGROUND Streptomyces fradiae is the principal producer of urdamycin A. The antibiotic consists of a polyketide-derived aglycone, which is glycosylated with four sugar components, 2x D-olivose (first and last sugar of a C-glycosidically bound trisaccharide chain at the 9-position), and 2x L-rhodinose (in the middle of the trisaccharide chain and at the 12b-position). Limited information is available about both the biosynthesis of D-olivose and L-rhodinose and the influence of the concentration of both sugars on urdamycin biosynthesis. RESULTS To further investigate urdamycin biosynthesis, a 5.4 kb section of the urdamycin biosynthetic gene cluster was sequenced. Five new open reading frames (ORFs) (urdZ3, urdQ, urdR, urdS, urdT) could be identified each one showing significant homology to deoxysugar biosynthetic genes. We inactivated four of these newly allocated ORFs (urdZ3, urdQ, urdR, urdS) as well as urdZ1, a previously found putative deoxysugar biosynthetic gene. Inactivation of urdZ3, urdQ and urdZ1 prevented the mutant strains from producing L-rhodinose resulting in the accumulation of mainly urdamycinone B. Inactivation of urdR led to the formation of the novel urdamycin M, which carries a C-glycosidically attached D-rhodinose at the 9-position. The novel urdamycins N and O were detected after overexpression of urdGT1c in two different chromosomal urdGT1c deletion mutants. The mutants lacking urdS and urdQ accumulated various known diketopiperazines. CONCLUSIONS Analysis of deoxysugar biosynthetic genes of the urdamycin biosynthetic gene cluster revealed a widely common biosynthetic pathway leading to D-olivose and L-rhodinose. Several enzymes responsible for specific steps of this pathway could be assigned. The pathway had to be modified compared to earlier suggestions. Two glycosyltransferases normally involved in the C-glycosyltransfer of D-olivose at the 9-position (UrdGT2) and in conversion of 100-2 to urdamycin G (UrdGT1c) show relaxed substrate specificity for their activated deoxysugar co-substrate and their alcohol substrate, respectively. They can transfer activated D-rhodinose (instead of D-olivose) to the 9-position, and attach L-rhodinose to the 4A-position normally occupied by a D-olivose unit, respectively.
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Affiliation(s)
- D Hoffmeister
- Christian-Albrechts-Universität zu Kiel. Pharmazeutische Biologie, Kiel, Germany
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19
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Affiliation(s)
- J Rohr
- Medical University of South Carolina Department of Pharmaceutical Sciences 171 Ashley Avenue, Charleston, SC 29425-2303 (USA)
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20
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Abstract
An 83-year-old Cambodian woman presented with multiple painful erythematous nodules on the lower legs, forearms and wrists. Subsequent history and investigations revealed a granulomatous lobular panniculitis associated with Sjögren's syndrome. This is a rare cutaneous association of Sjögrens syndrome with only three similar case reports in the literature.
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Affiliation(s)
- C P Tait
- Department of Dermatology, Royal Perth Hospital, Australia.
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21
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Rodriguez L, Oelkers C, Aguirrezabalaga I, Braña AF, Rohr J, Méndez C, Salas JA. Generation of hybrid elloramycin analogs by combinatorial biosynthesis using genes from anthracycline-type and macrolide biosynthetic pathways. J Mol Microbiol Biotechnol 2000; 2:271-6. [PMID: 10937435] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/17/2023] Open
Abstract
Elloramycin and oleandomycin are two polyketide compounds produced by Streptomyces olivaceus Tü2353 and Streptomyces antibioticus ATCC11891, respectively. Elloramycin is an anthracycline-like antitumor drug and oleandomycin a macrolide antibiotic. Expression in S. albus of a cosmid (cos16F4) containing part of the elloramycin biosynthetic gene cluster produced the elloramycin non-glycosylated intermediate 8-demethyl-tetracenomycin C. Several plasmid constructs harboring different gene combinations of L-oleandrose (neutral 2,6-dideoxyhexose attached to the macrolide antibiotic oleandomycin) biosynthetic genes of S. antibioticus that direct the biosynthesis of L-olivose, L-oleandrose and L-rhamnose were coexpressed with cos16F4 in S. albus. Three new hybrid elloramycin analogs were produced by these recombinant strains through combinatorial biosynthesis, containing elloramycinone or 12a-demethyl-elloramycinone (= 8-demethyl-tetracenomycin C) as aglycone moiety encoded by S. olivaceus genes and different sugar moieties, coded by the S. antibioticus genes. Among them is L-olivose, which is here described for the first time as a sugar moiety of a natural product.
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Affiliation(s)
- L Rodriguez
- Departamento de Biología Funcional e Instituto Universitario de Oncología del Principado de Asturias, Oviedo, Spain
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22
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Lozano MJ, Remsing LL, Quirós LM, Braña AF, Fernández E, Sánchez C, Méndez C, Rohr J, Salas JA. Characterization of two polyketide methyltransferases involved in the biosynthesis of the antitumor drug mithramycin by Streptomyces argillaceus. J Biol Chem 2000; 275:3065-74. [PMID: 10652287 DOI: 10.1074/jbc.275.5.3065] [Citation(s) in RCA: 56] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
A DNA chromosomal region of Streptomyces argillaceus ATCC 12596, the producer organism of the antitumor polyketide drug mithramycin, was cloned. Sequence analysis of this DNA region, located between four mithramycin glycosyltransferase genes, showed the presence of two genes (mtmMI and mtmMII) whose deduced products resembled S-adenosylmethionine-dependent methyltransferases. By independent insertional inactivation of both genes nonproducing mutants were generated that accumulated different mithramycin biosynthetic intermediates. The M3DeltaMI mutant (mtmMI-minus mutant) accumulated 4-demethylpremithramycinone (4-DPMC) which lacks the methyl groups at carbons 4 and 9. The M3DeltaM2 (mtmMII-minus mutant) accumulated 9-demethylpremithramycin A3 (9-DPMA3), premithramycin A1 (PMA1), and 7-demethylmithramycin, all of them containing the O-methyl group at C-4 and C-1', respectively, but lacking the methyl group at the aromatic position. Both genes were expressed in Streptomyces lividans TK21 under the control of the erythromycin resistance promoter (ermEp) of Saccharopolyspora erythraea. Cell-free extracts of these clones were precipitated with ammonium sulfate (90% saturation) and assayed for methylation activity using different mithramycin intermediates as substrates. Extracts of strains MJM1 (expressing the mtmMI gene) and MJM2 (expressing the mtmMII gene) catalyzed efficient transfer of tritium from [(3)H]S-adenosylmethionine into 4-DPMC and 9-DPMA3, respectively, being unable to methylate other intermediates at a detectable level. These results demonstrate that the mtmMI and mtmMII genes code for two S-adenosylmethionine-dependent methyltransferases responsible for the 4-O-methylation and 9-C-methylation steps of the biosynthetic precursors 4-DPMC and 9-DPMA3, respectively, of the antitumor drug mithramycin. A pathway is proposed for the last steps in the biosynthesis of mithramycin involving these methylation events.
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Affiliation(s)
- M J Lozano
- Departamento de Biología Funcional e Instituto Universitario de Oncología, Universidad de Oviedo, 33006 Oviedo, Spain
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23
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Lombó F, Künzel E, Prado L, Braña AF, Bindseil KU, Frevert J, Bearden D, Méndez C, Salas JA, Rohr J. The Novel Hybrid Antitumor Compound Premithramycinone H Provides Indirect Evidence for a Tricyclic Intermediate of the Biosynthesis of the Aureolic Acid Antibiotic Mithramycin. Angew Chem Int Ed Engl 2000; 39:796-799. [PMID: 10760873 DOI: 10.1002/(sici)1521-3773(20000218)39:4<796::aid-anie796>3.0.co;2-n] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- F Lombó
- Departamento de Biología Funcional e Instituto Universitario de Oncología del Principado de Asturias (IUOPA) Universidad de Oviedo 33006 Oviedo (Spain)
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24
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Trefzer A, Hoffmeister D, Künzel E, Stockert S, Weitnauer G, Westrich L, Rix U, Fuchser J, Bindseil KU, Rohr J, Bechthold A. Function of glycosyltransferase genes involved in urdamycin A biosynthesis. Chem Biol 2000; 7:133-42. [PMID: 10662691 DOI: 10.1016/s1074-5521(00)00079-x] [Citation(s) in RCA: 70] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
BACKGROUND Urdamycin A, the principle product of Streptomyces fradiae Tü2717, is an angucycline-type antibiotic. The polyketide-derived aglycone moiety is glycosylated at two positions, but only limited information is available about glycosyltransferases involved in urdamycin biosynthesis. RESULTS To determine the function of three glycosyltransferase genes in the urdamycin biosynthetic gene cluster, we have carried out gene inactivation and expression experiments. Inactivation of urdGT1a resulted in the predominant accumulation of urdamycin B. A mutant lacking urdGT1b and urdGT1c mainly produced compound 100-2. When urdGT1c was expressed in the urdGT1b/urdGT1c double mutant, urdamycin G and urdamycin A were detected. The mutant lacking all three genes mainly accumulated aquayamycin and urdamycinone B. Expression of urdGT1c in the triple mutant led to the formation of compound 100-1, whereas expression of urdGT1a resulted in the formation of compound 100-2. Co-expression of urdGT1b and urdGT1c resulted in the production of 12b-derhodinosyl-urdamycin A, and co-expression of urdGT1a, urdGT1b and urdGT1c resulted in the formation of urdamycin A. CONCLUSIONS Analysis of glycosyltransferase genes of the urdamycin biosynthetic gene cluster led to an unambiguous assignment of each glycosyltransferase to a certain biosynthetic saccharide attachment step.
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Affiliation(s)
- A Trefzer
- Pharmazeutische Biologie, Universität Tübingen, Pharmazeutisches Institut, Tübingen, D-72076, Germany
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25
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Faust B, Hoffmeister D, Weitnauer G, Westrich L, Haag S, Schneider P, Decker H, Künzel E, Rohr J, Bechthold A. Two new tailoring enzymes, a glycosyltransferase and an oxygenase, involved in biosynthesis of the angucycline antibiotic urdamycin A in Streptomyces fradiae Tü2717. Microbiology (Reading) 2000; 146 ( Pt 1):147-154. [PMID: 10658661 DOI: 10.1099/00221287-146-1-147] [Citation(s) in RCA: 79] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Urdamycin A, the principal product of Streptomyces fradiae Tu2717, is an angucycline-type antibiotic and anticancer agent containing C-glycosidically linked D-olivose. To extend knowledge of the biosynthesis of urdamycin A the authors have cloned further parts of the urdamycin biosynthetic gene cluster. Three new ORFs (urdK, urdJ and urdO) were identified on a 3.35 kb fragment, and seven new ORFs (urdL, urdM, urdJ2, urdZl, urdGT2, urdG and urdH) on an 8.05 kb fragment. The deduced products of these genes show similarities to transporters (urdJ and urdJ2), regulatory genes (urdK), reductases (urdO), cyclases (urdL) and deoxysugar biosynthetic genes (urdG, urdH and urdZ1). The product of urdM shows striking sequence similarity to oxygenases (N-terminal sequence) as well as reductases (C-terminal sequence), and the deduced amino acid sequence of urdGT2 resembles those of glycosyltransferases. To determine the function of urdM and urdGT2, targeted gene inactivation experiments were performed. The resulting urdM deletion mutant strains accumulated predominantly rabelomycin, indicating that UrdM is involved in oxygenation at position 12b of urdamycin A. A mutant in which urdGT2 had been deleted produced urdamycin I, urdamycin J and urdamycin K instead of urdamycin A. Urdamycins I, J and K are tetracyclic angucyclinones lacking a C-C connected deoxysugar moiety. Therefore UrdGT2 must catalyse the earliest glycosyltransfer step in the urdamycin biosynthetic pathway, the C-glycosyltransfer of one NDP-D-olivose.
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Affiliation(s)
- B Faust
- Universität Tübingen, Pharmazeutisches Institut, Auf der Morgenstelle 8, D-72076 Tübingen, Germany1
| | - D Hoffmeister
- Universität Tübingen, Pharmazeutisches Institut, Auf der Morgenstelle 8, D-72076 Tübingen, Germany1
| | - G Weitnauer
- Universität Tübingen, Pharmazeutisches Institut, Auf der Morgenstelle 8, D-72076 Tübingen, Germany1
| | - L Westrich
- Universität Tübingen, Pharmazeutisches Institut, Auf der Morgenstelle 8, D-72076 Tübingen, Germany1
| | - S Haag
- Hoechst Marion Roussel Deutschland GmbH, Process Development, D-65926 Frankfurt, Germany2
| | - P Schneider
- Universität Tübingen, Pharmazeutisches Institut, Auf der Morgenstelle 8, D-72076 Tübingen, Germany1
| | - H Decker
- Hoechst Marion Roussel Deutschland GmbH, Process Development, D-65926 Frankfurt, Germany2
| | - E Künzel
- Medical University of South Carolina, Department of Pharmaceutical Sciences, 171 Ashley Avenue, Charleston, SC 29425-2303, USA3
| | - J Rohr
- Medical University of South Carolina, Department of Pharmaceutical Sciences, 171 Ashley Avenue, Charleston, SC 29425-2303, USA3
| | - A Bechthold
- Universität Tübingen, Pharmazeutisches Institut, Auf der Morgenstelle 8, D-72076 Tübingen, Germany1
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26
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Blanco G, Fernández E, Fernández MJ, Braña AF, Weissbach U, Künzel E, Rohr J, Méndez C, Salas JA. Characterization of two glycosyltransferases involved in early glycosylation steps during biosynthesis of the antitumor polyketide mithramycin by Streptomyces argillaceus. Mol Gen Genet 2000; 262:991-1000. [PMID: 10660060 DOI: 10.1007/pl00008667] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
A 2,580-bp region of the chromosome of Streptomyces argillaceus, the producer of the antitumor polyketide mithramycin, was sequenced. Analysis of the nucleotide sequence revealed the presence of two genes (mtmGIII and mtmGIV) encoding proteins that showed a high degree of similarity to glycosyltransferases involved in the biosynthesis of various antibiotics and antitumor drugs. Independent insertional inactivation of both genes produced mutants that did not synthesize mithramycin but accumulated several mithramycin intermediates. Both mutants accumulated premithramycinone, a non-glycosylated intermediate in mithramycin biosynthesis. The mutant affected in the mtmGIII gene also accumulated premithramycin A1, which contains premithramycinone as the aglycon unit and a D-olivose attached at C-12a-O. These experiments demonstrate that the glycosyltransferases MtmGIV and MtmGIII catalyze the first two glycosylation steps in mithramycin biosynthesis. A model is proposed for the glycosylation steps in mithramycin biosynthesis.
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Affiliation(s)
- G Blanco
- Departamento de Biología Funcional e Instituto Universitario de Oncología del Principado de Asturias, Universidad de Oviedo, Spain
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27
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Prado L, Lombó F, Braña AF, Méndez C, Rohr J, Salas JA. Analysis of two chromosomal regions adjacent to genes for a type II polyketide synthase involved in the biosynthesis of the antitumor polyketide mithramycin in Streptomyces argillaceus. Mol Gen Genet 1999; 261:216-25. [PMID: 10102355 DOI: 10.1007/s004380050960] [Citation(s) in RCA: 45] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Abstract
Mithramycin is an aromatic antitumour polyketide synthesized by Streptomyces argillaceus. Two chromosomal regions located upstream and downstream of the locus for the mithramycin type II polyketide synthase were cloned and sequenced. Analysis of the sequence revealed the presence of eight genes encoding three oxygenases (mtmOI, mtmOII and mtmOIII), three reductases (mtmTI, mtmTII and mtmTIII), a cyclase (mtm Y) and an acyl CoA ligase (mtmL). The three oxygenase genes were each inactivated by gene replacement. Inactivation of one of them (mtmOII) generated a non-producing mutant, while inactivation of the other two (mtmOl and mtmOIII) did not affect the biosynthesis of mithramycin. The mtmOII gene may code for an oxygenase responsible for the introduction of oxygen atoms at early steps in the biosynthesis of mithramycin leading to 4-demethylpremithramycinone. One of the reductases may be responsible for reductive cleavage of an intermediate from an enzyme and another for the reduction of a keto group in the side-chain of the mithramycin aglycon moiety. A hypothetical biosynthetic pathway showing in particular the involvement of oxygenase MtmOII and of various other gene products in mithramycin biosynthesis is proposed.
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Affiliation(s)
- L Prado
- Departamento de Biología Funcional e Instituto Universitario de Biotecnología de Asturias (I.U.B.A-C.S.I.C) Universidad de Oviedo, Spain
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28
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Prado L, Fernández E, Weissbach U, Blanco G, Quirós LM, Braña AF, Méndez C, Rohr J, Salas JA. Oxidative cleavage of premithramycin B is one of the last steps in the biosynthesis of the antitumor drug mithramycin. Chem Biol 1999; 6:19-30. [PMID: 9889148 DOI: 10.1016/s1074-5521(99)80017-9] [Citation(s) in RCA: 68] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/16/2022]
Abstract
BACKGROUND Mithramycin is a member of the clinically important aureolic acid group of antitumor drugs that interact with GC-rich regions of DNA nonintercalatively. These drugs contain a chromophore aglycon that is derived from condensation of ten acetate units (catalyzed by a type II polyketide synthase). The aglycones are glycosylated at two positions with different chain length deoxyoligosaccharides, which are essential for the antitumor activity. During the early stages of mithramycin biosynthesis, tetracyclic intermediates of the tetracycline-type occur, which must be converted at later stages into the tricyclic glycosylated molecule, presumably through oxidative breakage of the fourth ring. RESULTS Two intermediates in the mithramycin biosynthetic pathway, 4-demethyl-premithramycinone and premithramycin B, were identified in a mutant lacking the mithramycin glycosyltransferase and methyltransferase genes and in the same mutant complemented with the deleted genes, respectively. Premithramycin B contains five deoxysugars moieties (like mithramycin), but contains a tetracyclic aglycon moiety instead of a tricyclic aglycon. We hypothesized that transcription of mtmOIV (encoding an oxygenase) was impaired in this strain, preventing oxidative breakage of the fourth ring of premithramycin B. Inactivating mtmOIV generated a mithramycin nonproducing mutant that accumulated premithramycin B instead of mithramycin. In vitro assays demonstrated that MtmOIV converted premithramycin B into a tricyclic compound. CONCLUSIONS In the late stages of mithramycin biosynthesis by Strepyomyces argillaceus, a fully glycosylated tetracyclic tetracycline-like intermediate (premithramycin B) is converted into a tricyclic compound by the oxygenase MtmOIV. This oxygenase inserts an oxygen (Baeyer-Villiger oxidation) and opens the resulting lactone. The following decarboxylation and ketoreduction steps lead to mithramycin. Opening of the fourth ring represents one of the last steps in mithramycin biosynthesis.
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Affiliation(s)
- L Prado
- Departamento de Biología Funcional e Instituto Universitario de Biotecnología de Asturias (IUBA-CSIC), Universidad de Oviedo, 33006 Oviedo, Spain
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Abstract
A reinvestigation of the structure of mithramycin, the principal product of Streptomyces argillaceus ATCC 12956, is reported. The structure elucidation was carried out with mithramycin decaacetate (4) using 2D NMR methods, including TOCSY, HMBC, and HSQC experiments. The work resulted in structure 3being confirmed for mithramycin.
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Affiliation(s)
- S E Wohlert
- Medical University of South Carolina, Department of Pharmaceutical Sciences, 171 Ashley Avenue, Charleston, South Carolina 29425-2303, USA
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Wohlert SE, Blanco G, Lombó F, Fernández E, Braña AF, Reich S, Udvarnoki G, Méndez C, Decker H, Frevert J, Salas JA, Rohr J. Novel Hybrid Tetracenomycins through Combinatorial Biosynthesis Using a Glycosyltransferase Encoded by the elm Genes in Cosmid 16F4 and Which Shows a Broad Sugar Substrate Specificity. J Am Chem Soc 1998. [DOI: 10.1021/ja981687e] [Citation(s) in RCA: 49] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- S.-E. Wohlert
- Contribution from the Medical University of South Carolina, Department of Pharmaceutical Sciences, 171 Ashley Avenue, Charleston, South Carolina 29425-2303, Institut für Organische Chemie der Universität, Tammannstrasse 2, D-37077 Göttingen, Germany, Departamento de Biología Funcional e Instituto Universitario de Biotecnologia de Asturias, Universidad de Oviedo, E-33006 Oviedo, Spain, Hoechst AG, Abteilung Neue Produkte H-780, D-65926 Frankfurt, Germany, and AnalytiCon AG, Hermannswerder Haus 17, D-14473
| | - G. Blanco
- Contribution from the Medical University of South Carolina, Department of Pharmaceutical Sciences, 171 Ashley Avenue, Charleston, South Carolina 29425-2303, Institut für Organische Chemie der Universität, Tammannstrasse 2, D-37077 Göttingen, Germany, Departamento de Biología Funcional e Instituto Universitario de Biotecnologia de Asturias, Universidad de Oviedo, E-33006 Oviedo, Spain, Hoechst AG, Abteilung Neue Produkte H-780, D-65926 Frankfurt, Germany, and AnalytiCon AG, Hermannswerder Haus 17, D-14473
| | - F. Lombó
- Contribution from the Medical University of South Carolina, Department of Pharmaceutical Sciences, 171 Ashley Avenue, Charleston, South Carolina 29425-2303, Institut für Organische Chemie der Universität, Tammannstrasse 2, D-37077 Göttingen, Germany, Departamento de Biología Funcional e Instituto Universitario de Biotecnologia de Asturias, Universidad de Oviedo, E-33006 Oviedo, Spain, Hoechst AG, Abteilung Neue Produkte H-780, D-65926 Frankfurt, Germany, and AnalytiCon AG, Hermannswerder Haus 17, D-14473
| | - E. Fernández
- Contribution from the Medical University of South Carolina, Department of Pharmaceutical Sciences, 171 Ashley Avenue, Charleston, South Carolina 29425-2303, Institut für Organische Chemie der Universität, Tammannstrasse 2, D-37077 Göttingen, Germany, Departamento de Biología Funcional e Instituto Universitario de Biotecnologia de Asturias, Universidad de Oviedo, E-33006 Oviedo, Spain, Hoechst AG, Abteilung Neue Produkte H-780, D-65926 Frankfurt, Germany, and AnalytiCon AG, Hermannswerder Haus 17, D-14473
| | - A. F. Braña
- Contribution from the Medical University of South Carolina, Department of Pharmaceutical Sciences, 171 Ashley Avenue, Charleston, South Carolina 29425-2303, Institut für Organische Chemie der Universität, Tammannstrasse 2, D-37077 Göttingen, Germany, Departamento de Biología Funcional e Instituto Universitario de Biotecnologia de Asturias, Universidad de Oviedo, E-33006 Oviedo, Spain, Hoechst AG, Abteilung Neue Produkte H-780, D-65926 Frankfurt, Germany, and AnalytiCon AG, Hermannswerder Haus 17, D-14473
| | - S. Reich
- Contribution from the Medical University of South Carolina, Department of Pharmaceutical Sciences, 171 Ashley Avenue, Charleston, South Carolina 29425-2303, Institut für Organische Chemie der Universität, Tammannstrasse 2, D-37077 Göttingen, Germany, Departamento de Biología Funcional e Instituto Universitario de Biotecnologia de Asturias, Universidad de Oviedo, E-33006 Oviedo, Spain, Hoechst AG, Abteilung Neue Produkte H-780, D-65926 Frankfurt, Germany, and AnalytiCon AG, Hermannswerder Haus 17, D-14473
| | - G. Udvarnoki
- Contribution from the Medical University of South Carolina, Department of Pharmaceutical Sciences, 171 Ashley Avenue, Charleston, South Carolina 29425-2303, Institut für Organische Chemie der Universität, Tammannstrasse 2, D-37077 Göttingen, Germany, Departamento de Biología Funcional e Instituto Universitario de Biotecnologia de Asturias, Universidad de Oviedo, E-33006 Oviedo, Spain, Hoechst AG, Abteilung Neue Produkte H-780, D-65926 Frankfurt, Germany, and AnalytiCon AG, Hermannswerder Haus 17, D-14473
| | - C. Méndez
- Contribution from the Medical University of South Carolina, Department of Pharmaceutical Sciences, 171 Ashley Avenue, Charleston, South Carolina 29425-2303, Institut für Organische Chemie der Universität, Tammannstrasse 2, D-37077 Göttingen, Germany, Departamento de Biología Funcional e Instituto Universitario de Biotecnologia de Asturias, Universidad de Oviedo, E-33006 Oviedo, Spain, Hoechst AG, Abteilung Neue Produkte H-780, D-65926 Frankfurt, Germany, and AnalytiCon AG, Hermannswerder Haus 17, D-14473
| | - H. Decker
- Contribution from the Medical University of South Carolina, Department of Pharmaceutical Sciences, 171 Ashley Avenue, Charleston, South Carolina 29425-2303, Institut für Organische Chemie der Universität, Tammannstrasse 2, D-37077 Göttingen, Germany, Departamento de Biología Funcional e Instituto Universitario de Biotecnologia de Asturias, Universidad de Oviedo, E-33006 Oviedo, Spain, Hoechst AG, Abteilung Neue Produkte H-780, D-65926 Frankfurt, Germany, and AnalytiCon AG, Hermannswerder Haus 17, D-14473
| | - J. Frevert
- Contribution from the Medical University of South Carolina, Department of Pharmaceutical Sciences, 171 Ashley Avenue, Charleston, South Carolina 29425-2303, Institut für Organische Chemie der Universität, Tammannstrasse 2, D-37077 Göttingen, Germany, Departamento de Biología Funcional e Instituto Universitario de Biotecnologia de Asturias, Universidad de Oviedo, E-33006 Oviedo, Spain, Hoechst AG, Abteilung Neue Produkte H-780, D-65926 Frankfurt, Germany, and AnalytiCon AG, Hermannswerder Haus 17, D-14473
| | - J. A. Salas
- Contribution from the Medical University of South Carolina, Department of Pharmaceutical Sciences, 171 Ashley Avenue, Charleston, South Carolina 29425-2303, Institut für Organische Chemie der Universität, Tammannstrasse 2, D-37077 Göttingen, Germany, Departamento de Biología Funcional e Instituto Universitario de Biotecnologia de Asturias, Universidad de Oviedo, E-33006 Oviedo, Spain, Hoechst AG, Abteilung Neue Produkte H-780, D-65926 Frankfurt, Germany, and AnalytiCon AG, Hermannswerder Haus 17, D-14473
| | - J. Rohr
- Contribution from the Medical University of South Carolina, Department of Pharmaceutical Sciences, 171 Ashley Avenue, Charleston, South Carolina 29425-2303, Institut für Organische Chemie der Universität, Tammannstrasse 2, D-37077 Göttingen, Germany, Departamento de Biología Funcional e Instituto Universitario de Biotecnologia de Asturias, Universidad de Oviedo, E-33006 Oviedo, Spain, Hoechst AG, Abteilung Neue Produkte H-780, D-65926 Frankfurt, Germany, and AnalytiCon AG, Hermannswerder Haus 17, D-14473
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Fernández E, Weissbach U, Sánchez Reillo C, Braña AF, Méndez C, Rohr J, Salas JA. Identification of two genes from Streptomyces argillaceus encoding glycosyltransferases involved in transfer of a disaccharide during biosynthesis of the antitumor drug mithramycin. J Bacteriol 1998; 180:4929-37. [PMID: 9733697 PMCID: PMC107519 DOI: 10.1128/jb.180.18.4929-4937.1998] [Citation(s) in RCA: 160] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Mithramycin is an antitumor polyketide drug produced by Streptomyces argillaceus that contains two deoxysugar chains, a disaccharide consisting of two D-olivoses and a trisaccharide consisting of a D-olivose, a D-oliose, and a D-mycarose. From a cosmid clone (cosAR3) which confers resistance to mithramycin in streptomycetes, a 3-kb PstI-XhoI fragment was sequenced, and two divergent genes (mtmGI and mtmGII) were identified. Comparison of the deduced products of both genes with proteins in databases showed similarities with glycosyltransferases and glucuronosyltransferases from different sources, including several glycosyltransferases involved in sugar transfer during antibiotic biosynthesis. Both genes were independently inactivated by gene replacement, and the mutants generated (M3G1 and M3G2) did not produce mithramycin. High-performance liquid chromatography analysis of ethyl acetate extracts of culture supernatants of both mutants showed the presence of several peaks with the characteristic spectra of mithramycin biosynthetic intermediates. Four compounds were isolated from both mutants by preparative high-performance liquid chromatography, and their structures were elucidated by physicochemical methods. The structures of these compounds were identical in both mutants, and the compounds are suggested to be glycosylated intermediates of mithramycin biosynthesis with different numbers of sugar moieties attached to C-12a-O of a tetracyclic mithramycin precursor and to C-2-O of mithramycinone: three tetracyclic intermediates containing one sugar (premithramycin A1), two sugars (premithramycin A2), or three sugars (premithramycin A3) and one tricyclic intermediate containing a trisaccharide chain (premithramycin A4). It is proposed that the glycosyltransferases encoded by mtmGI and mtmGII are responsible for forming and transferring the disaccharide during mithramycin biosynthesis. From the structures of the new metabolites, a new biosynthetic sequence regarding late steps of mithramycin biosynthesis can be suggested, a sequence which includes glycosyl transfer steps prior to the final shaping of the aglycone moiety of mithramycin.
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Affiliation(s)
- E Fernández
- Departamento de Biología Funcional e Instituto Universitario de Biotecnologia de Asturias, Universidad de Oviedo, 33006 Oviedo, Spain
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32
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Abstract
Flow-induced bioluminescence provides a unique opportunity for visualizing the flow field around a swimming dolphin. Unfortunately, previous descriptions of dolphin-stimulated bioluminescence have been largely anecdotal and often conflicting. Most references in the scientific literature report an absence of bioluminescence on the dolphin body, which has been invariably assumed to be indicative of laminar flow. However, hydrodynamicists have yet to find compelling evidence that the flow remains laminar over most of the body. The present study integrates laboratory, computational and field approaches to begin to assess the utility of using bioluminescence as a method for flow visualization by relating fundamental characteristics of the flow to the stimulation of naturally occurring luminescent plankton. Laboratory experiments using fully developed pipe flow revealed that the bioluminescent organisms identified in the field studies can be stimulated in both laminar and turbulent flow when shear stress values exceed approximately 0.1 N m-2. Computational studies of an idealized hydrodynamic representation of a dolphin (modeled as a 6:1 ellipsoid), gliding at a speed of 2 m s-1, predicted suprathreshold surface shear stress values everywhere on the model, regardless of whether the boundary layer flow was laminar or turbulent. Laboratory flow visualization of a sphere demonstrated that the intensity of bioluminescence decreased with increasing flow speed due to the thinning of the boundary layer, while flow separation caused a dramatic increase in intensity due to the significantly greater volume of stimulating flow in the wake. Intensified video recordings of dolphins gliding at speeds of approximately 2 m s-1 confirmed that brilliant displays of bioluminescence occurred on the body of the dolphin. The distribution and intensity of bioluminescence suggest that the flow remained attached over most of the body. A conspicuous lack of bioluminescence was often observed on the dolphin rostrum and melon and on the leading edge of the dorsal and pectoral fins, where the boundary layer is thought to be thinnest. To differentiate between effects related to the thickness of the stimulatory boundary layer and those due to the latency of the bioluminescence response and the upstream depletion of bioluminescence, laboratory and dolphin studies of forced separation and laminar-to-turbulent transition were conducted. The observed pattern of stimulated bioluminescence is consistent with the hypothesis that bioluminescent intensity is directly related to the thickness of the boundary layer.
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Affiliation(s)
- J Rohr
- SPAWARSYSCEN, San Diego, CA 92152-5000, USA.
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Meurer G, Gerlitz M, Wendt-Pienkowski E, Vining LC, Rohr J, Hutchinson CR. Iterative type II polyketide synthases, cyclases and ketoreductases exhibit context-dependent behavior in the biosynthesis of linear and angular decapolyketides. Chem Biol 1997; 4:433-43. [PMID: 9224566 DOI: 10.1016/s1074-5521(97)90195-2] [Citation(s) in RCA: 48] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
BACKGROUND Iterative type II polyketide synthases (PKSs) produce polyketide chains of variable but defined length from a specific starter unit and a number of extender units. They also specify the initial regiospecific folding and cyclization pattern of nascent polyketides either through the action of a cyclase (CYC) subunit or through the combined action of site-specific ketoreductase (KR) and CYC subunits. Additional CYCs and other modifications may be necessary to produce linear aromatic polyketides. The principles of the assembly of the linear aromatic polyketides, several of which are medically important, are well understood, but it is not clear whether the assembly of the angular aromatic (angucyclic) polyketides follows the same rules. RESULTS We performed an in vivo evaluation of the subunits of the PKS responsible for the production of the angucyclic polyketide jadomycin (jad), in comparison with their counterparts from the daunorubicin (dps) and tetracenomycin (tcm) PKSs which produce linear aromatic polyketides. No matter which minimal PKS was used to produce the initial polyketide chain, the JadD and DpsF CYCs produced the same two polyketides, in the same ratio; neither product was angularly fused. The set of jadABCED PKS plus putative jadl CYC genes behaved similarly. Furthermore, no angular polyketides were isolated when the entire set of jad PKS enzymes and Jadl or the jad minimal PKS, Jadl and the TcmN CYC were present. The DpsE KR was able to reduce decaketides but not octaketides; in contrast, the KRs from the jad PKS (JadE) or the actinorhodin PKS (ActIII) could reduce octaketide chains, giving three distinct products. CONCLUSIONS It appears that the biosynthesis of angucyclic polyketides cannot be simply accomplished by expressing the known PKS subunits from artificial gene cassettes under the control of a non-native promoter. The characteristic structure of the angucycline ring system may arise from a kinked precursor during later cyclization reactions involving additional, but so far unknown, components of the extended decaketide PKS. Our results also suggest that some KRs have a minimal chain length requirement and that CYC enzymes may act aberrantly as first-ring aromatases that are unable to perform all of the sequential cyclization steps. Both of these characteristics may limit the widespread application of CYC or KR enzymes in the synthesis of novel polyketides.
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Affiliation(s)
- G Meurer
- School of Pharmacy, University of Wisconsin, 425 N. Charter St, Madison, WI 53706, USA
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34
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Affiliation(s)
- B Frank
- Department of Health Restoration, Indiana State University School of Nursing, Terre Haute, USA
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35
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Rohr J, Kittner S, Feeser B, Hebel JR, Whyte MG, Weinstein A, Kanarak N, Buchholz D, Earley C, Johnson C, Macko R, Price T, Sloan M, Stern B, Wityk R, Wozniak M, Sherwin R. Traditional risk factors and ischemic stroke in young adults: the Baltimore-Washington Cooperative Young Stroke Study. Arch Neurol 1996; 53:603-7. [PMID: 8929167 DOI: 10.1001/archneur.1996.00550070041010] [Citation(s) in RCA: 93] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
OBJECTIVE To determine the association of hypertension, diabetes, and cigarette smoking with incidence of ischemic stroke in young adults. DESIGN Case-control study. SETTING Population-based sample of cases and controls. SUBJECTS The study included 296 cases of incident ischemic stroke among black and white adults aged 18 to 44 years in central Maryland counties from the Baltimore-Washington Cooperative Young Stroke Study and 1220 black and white adults aged 18 to 44 years from the Maryland Behavioral Risk Factor Survey, a telephone survey of a random sample of the same region, to serve as controls. MAIN OUTCOME MEASURES Logistic regression models were developed to determine the age-adjusted odds ratios for each risk factor. Population-attributable risk percent were computed based on the odds ratios and prevalence of each risk factor. RESULTS The age-adjusted odds ratios (95% confidence intervals) for white men (WM), white women (WW), black men (BM), and black women (BW) were as follows: current cigarette smoking: WM, 2.0 (1.1-3.8), WW, 2.1 (1.1-4.3), BM, 3.3 (1.6-6.6), and BW, 2.2 (1.3-3.9); history of diabetes mellitus: WM, 22.9 (5.8-89.6), WW, 6.2 (1.9-20.2), BM, 4.2 (0.8-21.9), and BW, 3.3 (1.4-7.7); and history of hypertension: WM, 1.6 (0.7-3.2), WW, 2.5 (1.1-5.9), BM, 3.8 (1.8-7.9), and BW, 4.2 (2.4-7.5). The population-attributable risk percent (95% confidence intervals) were as follows: current cigarette smoking: WM, 22.6 (3.1-38.2), WW, 17.2 (4.0-34.0), BM, 40.5 (23.1-54.0), and BW, 29.1 (13.5-41.9); history of diabetes mellitus: WM, 19.0 (8.2-28.5), WW, 15.8 (3.8-26.3), BM, 13.2 (5.3-20.4), and BW, 22.1 (12.5-30.7); and history of hypertension: WM, 21.7 (6.2-34.6), WW, 21.3 (5.4-34.5), BM, 53.5 (39.0-64.4), and BW, 50.5 (37.1-61.1). CONCLUSIONS Hypertension, diabetes mellitus, and current cigarette smoking are important risk factors in a biracial young adult population. Cigarette smoking and hypertension, the 2 most modifiable risk factors, were particularly important risk factors in young blacks.
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Affiliation(s)
- J Rohr
- Department of Neurology, University of Maryland Medical School, Baltimore 21201-1559, USA
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Blum S, Groth I, Rohr J, Fielder HP. Biosynthetic capacities of actinomycetes. 5. Dioxolides, novel secondary metabolites from Streptomyces tendae. J Basic Microbiol 1996; 36:19-25. [PMID: 8819841 DOI: 10.1002/jobm.3620360105] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Dioxolides, a novel class of secondary metabolites were detected by a HPLC-diode array screening technique in the culture filtrate of Streptomyces tendae Tu 4042. The compounds show no biological activity against Gram-positive and Gram-negative bacteria, yeasts and fungi. Besides dioxolides, which consist of an unusual substituted dioxolane ring, anhydroshikimate and para-hydrobenzamide were detected by this technique. Both compounds were not yet described as natural products.
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Affiliation(s)
- S Blum
- Biologisches Institut, Universitaet Tuebingen, Germany
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Decker H, Rohr J, Motamedi H, Zähner H, Hutchinson CR. Identification of Streptomyces olivaceus Tü 2353 genes involved in the production of the polyketide elloramycin. Gene 1995; 166:121-6. [PMID: 8529875 DOI: 10.1016/0378-1119(95)00573-7] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
The genes for the production of elloramycin (ELM) from Streptomyces olivaceus (So) Tü2353 were cloned using a polyketide synthase gene probe from the tetracenomycin pathway. A cosmid clone (16F4) isolated from a gene library of So Tü2353 conferred tetracenomycin C and ELM resistance to S. lividans TK64 and complemented a mutation in So Tü2353R. Introduction of cosmid 16F4 into S. lividans TK64 resulted in the production of 8-demethyl-tetracenomycin C, an intermediate of ELM biosynthesis.
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Affiliation(s)
- H Decker
- Biologisches Institut, Universität Tübingen, Germany
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38
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Affiliation(s)
- E Egert
- Institut für Anorganische Chemie, Universität Göttingen, FRG
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40
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Affiliation(s)
- J Rohr
- Institut für Organische Chemie, Universität Göttingen, F.R.G
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Abstract
The structure-activity relationships of the anthracycline-related antibiotics of the tetracenomycin C/elloramycin-type were investigated by derivatization of elloramycin (1) and elloramycinone (2). During hydrolysis experiments a unique transglycosylation reaction was discovered, converting elloramycin (1) into isoelloramycin (10) by treatment with anhydrous trifluoroacetic acid. Following the proposed structure-activity relationship concept, 8-O-methylelloramycinone (14) was synthesized from elloramycinone (2), and was shown to be the most active derivative according to the proliferation inhibition assay against murine L1210 leukemia cells.
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Affiliation(s)
- J Rohr
- Institut für Organische Chemie, Universität Göttingen, W. Germany
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Henkel T, Rohr J, Beale JM, Schwenen L. Landomycins, new angucycline antibiotics from Streptomyces sp. I. Structural studies on landomycins A-D. J Antibiot (Tokyo) 1990; 43:492-503. [PMID: 2358402 DOI: 10.7164/antibiotics.43.492] [Citation(s) in RCA: 103] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
The chemical structure of the new angucycline antibiotic landomycin A has been elucidated via chemical and spectroscopic methods, in particular by 2D NMR correlation spectroscopy, e.g., 1H, 1H-COSY, 13C, 1H-COSY, correlation spectroscopy via long-range-couplings and heteronuclear multiple bond connectivity spectroscopy sequences. The spectroscopic investigations were carried out principally with the octaacetyl derivative of landomycin A, which is more soluble in organic solvents than landomycin A itself. The structure consists of a new, unusual angucyclinone, landomycinone A, and of six deoxy sugars, four D-olivoses and two L-rhodinoses, which are all assembled in one chain thus forming the sequence (olivose-4----1-olivose-3----1-rhodinose)2. This long sugar chain is bonded as a phenolic glycoside to the aglycone moiety, a unique structural feature among quinone glycoside antibiotics. By comparison with the main component landomycin A, the structures of three minor congeners, namely landomycins B, C and D, could be proposed.
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Affiliation(s)
- T Henkel
- Institut für Organische Chemie, Universität Göttingen, W. Germany
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Rohr J. Urdamycins, new angucycline antibiotics from Streptomyces fradiae. VI. Structure elucidation and biosynthetic investigations on urdamycin H. J Antibiot (Tokyo) 1989; 42:1482-8. [PMID: 2808135 DOI: 10.7164/antibiotics.42.1482] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
A new angucycline antibiotic has been discovered as a small side product of Streptomyces fradiae (strain Tü 2717), the producer of the urdamycin complex, during screening for biosynthetic relatives of urdamycins C and D. The structure was elucidated after isolation, via strain selection, of a mutant of S. fradiae that produces this new congener in larger amounts. The structure includes a new chromophore containing aglycone that has not been found before among the angucyclines nor as a natural product generally. In urdamycin H (1) the angucycline four-ring system is enlarged by a (p-OH-phenyl)furan moiety and is closely related to urdamycin C (2). The structure was elucidated by comparison of the physico-chemical data with those of known urdamycins, especially with those of urdamycin C (2), and was confirmed by intensive 2D NMR analysis. Biosynthetic studies showed that tyrosine and not the smaller p-OH-phenylglycine is the precursor of the (p-OH-phenyl)furan moiety.
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Affiliation(s)
- J Rohr
- Institut für Organische Chemie Universität Göttingen
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Abstract
The biogenetic origin of the angucycline antibiotics urdamycins A-D was studied by feeding experiments with isotope labeled precursors and by NMR analysis. Feeding experiments with [1-13C]acetate and [1,2-13C2]acetate show that the chromophores of urdamycins A and B and the angucycline 4-ring skeleton of the urdamycins C and D chromophores are formed from a single decapolyketide chain. The chromophores of the urdamycins C and D contain additional structural elements which derived from the amino acids tyrosine and tryptophan, respectively. The latter was shown by feeding deuterium-labeled tyrosine and 13C-labeled tryptophan derivatives. Feeding of [1-13C]glucose and of [U-13C3]glycerol proved that the C-glycosidic moiety and the three sugars (2 x L-rhodinose, 1 x D-olivose each) of the urdamycins arise from glucose. Experiments with 14C-labeled urdamycin A, obtained by biosynthesis from [14C]acetate, showed this compound to be a late precursor of the urdamycins C and D.
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Affiliation(s)
- J Rohr
- Institut für Organische Chemie, Universität Göttingen, West Germany
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45
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Abstract
Derivatives of the angucycline urdamycin A (1) were prepared in order to study structure-activity relationships in this group of antitumor antibiotics. Derivatives of 1 formed by methanolysis, O-acylation, hydrogenation and treatment with diazomethane were isolated and characterized by their spectroscopic data. Urdamycin G (20) was isolated from Streptomyces fradiae by shortening the fermentation time. The different glycosidation pattern of the aglycone 14 did not lead to significant differences in the biological activity. O-Acylation was shown to enhance the in vitro activity of 1 against stem cells of murine L1210 leukemia depending on the lipophilicity of the molecules. The importance of the 5,6-double bond of 1 with regard to the antitumor activities is discussed.
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Affiliation(s)
- T Henkel
- Institut für Organische Chemie, Universität Göttingen, FRG
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Rohr J, Eick S, Zeeck A, Reuschenbach P, Zähner H, Fiedler HP. Metabolic products of microorganisms. 249. Tetracenomycins B3 and D3, key intermediates of the elloramycin and tetracenomycin C biosynthesis. J Antibiot (Tokyo) 1988; 41:1066-73. [PMID: 3170342 DOI: 10.7164/antibiotics.41.1066] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Tetracenomycins B3 and D3, besides tetracenomycin D (D1), were produced by a blocked mutant of the elloramycin producer Streptomyces olivaceus TU 2353. The compounds were isolated as red powders, and their structures were elucidated by comparing their physicochemical data with those of the known tetracenomycins A2, B1, B2, D and E. Tetracenomycin B3 (2), the main compound, and tetracenomycin D (3) were antibiotically inactive against Gram-positive and Gram-negative bacteria, whereas tetracenomycin D3 (1) showed a moderate activity against Bacillus subtilis and Arthrobacter aurescens. Tetracenomycin B3 (2) is the key intermediate where the biosynthesis of the elloramycins branches off from the line leading to tetracenomycin C (5) as the final product of the tetracenomycin biosynthesis branch.
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Affiliation(s)
- J Rohr
- Universität Göttingen, Institut für Organische Chemie, FRG
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47
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Affiliation(s)
- J Rohr
- Institut für Organische Chemie, Universität Göttingen, West Germany
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48
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Ricou F, Gabathuler J, Aebischer N, Rohr J, Lerch R, Rutishauser W. [Echocardiographic discoveries in 102 patients with vascular cerebral accidents]. Arch Mal Coeur Vaiss 1987; 80:1151-7. [PMID: 3118839] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
The causes of vascular ischaemic accidents are numerous, and when the brain is involved management is limited to the prevention of similar events. Since cardiac sources of embolism potentially curable, we have prospectively analyzed the results of cardiovascular examinations (including ECG and radiography of the chest) and of echocardiography in 102 patients with cerebral or peripheral vascular ischaemic event in order to determine the impact of echocardiography and the influence of different diagnoses on the need for anticoagulant therapy. Intracardiac thrombi, mitral stenosis, dilated cardiomyopathy, severe left ventricular dysfunction with or without aneurysm and cardiac valve vegetations were regarded as diseases carrying a high risk of embolism, the low risk diseases being mitral valve prolapse, mitral annulus calcification and isolated left atrial dilatation. Atrial fibrillation was treated separately, as it may be associated with several of the diseases listed above. We found 14 diseases with a high risk of embolism (14 p. 100) and 35 diseases with a low risk of embolism (34 p. 100). 10/91 patients with cerebral vascular accident (11 p. 100) and 4/11 patients with peripheral vascular accident presented with a heart disease carrying a high risk of embolism. The most common heart disease with a high risk of embolism (10/14, 71 p. 100) was severe left ventricular dysfunction secondary to a coronary disease or a dilated cardiomyopathy. We did not find more cases of mitral valve prolapse or mitral annulus calcification than in the normal population. 20/29 patients with normal cardiac examination had a normal echocardiogram. The anticoagulant treatment was modified after echocardiography in only one case.(ABSTRACT TRUNCATED AT 250 WORDS)
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Affiliation(s)
- F Ricou
- Centre de cardiologie, hôpital Cantonal Universitaire de Genève
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Rohr J, Zeeck A. Metabolic products of microorganisms. 240. Urdamycins, new angucycline antibiotics from Streptomyces fradiae. II. Structural studies of urdamycins B to F. J Antibiot (Tokyo) 1987; 40:459-67. [PMID: 3583915 DOI: 10.7164/antibiotics.40.459] [Citation(s) in RCA: 52] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
The structures of the angucycline antibiotics urdamycin B (5), E (2) and F (9) were established by comparing of their spectra with those of urdamycin A (1). The structures of urdamycins C and D, the largest compounds of this series, are still incomplete (10 and 11). The aglycones urdamycinone C, D and E can be liberated by methanolysis of the corresponding urdamycins. The liberation of urdamycinone B (6) requires an alcohol-free medium, to prevent its rearrangement to the naphthacenequinone 7 or 8. The urdamycins differ from other O-glycoside series in their variety of aglycones.
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von Segesser L, Rohr J, Simonet F, Aymon E, Faidutti B. [Recurrent carotid stenosis]. Rev Med Suisse Romande 1987; 107:273-6. [PMID: 3589320] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
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