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Moore MJ, Qin P, Yamasaki N, Zeng X, Keith DJ, Jung S, Fukazawa T, Graham-O’Regan K, Wu ZC, Chatterjee S, Boger DL. Tetrachlorovancomycin: Total Synthesis of a Designed Glycopeptide Antibiotic of Reduced Synthetic Complexity. J Am Chem Soc 2023; 145:21132-21141. [PMID: 37721995 PMCID: PMC10538376 DOI: 10.1021/jacs.3c08358] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/20/2023]
Abstract
A technically straightforward total synthesis of a new class of vancomycin analogues of reduced synthetic complexity was developed that provided tetrachlorovancomycin (1, LLS = 15 steps, 15% overall yield) and its precursor aglycon 29 (nearly 20% overall yield). The class retains all the intricate vancomycin structural features that contribute to its target binding affinity and selectivity, maintains the antimicrobial activity of vancomycin, and achieves the simplification by an unusual addition, not removal, of benign substituents to the core structure. The modification, accomplished by addition of two aryl chloride substituents to provide 1, permitted a streamlined total synthesis of the new glycopeptide antibiotic class by removing the challenges associated with CD and DE ring system atropisomer stereochemical control. This also enabled their simultaneous and further-activated SNAr macrocyclizations that establish the tricyclic skeleton of 1. Key elements of the approach include catalyst-controlled diastereoselective formation of the AB biaryl axis of chirality (>30:1 dr), an essentially instantaneous macrolactamization of the AB ring system free of competitive epimerization (>30:1 dr), racemization free coupling of the E ring tetrapeptide, room temperature simultaneous CD and DE ring system cyclizations, a highly refined 4-step conversion of the cyclization product to the aglycon, and a protecting-group-free one-pot enzymatic glycosylation for disaccharide introduction. In addition to the antimicrobial evaluation of tetrachlorovancomycin (1), the preparation of key peripherally modified derivatives, which introduce independent and synergistic mechanisms of action, revealed their exceptional antimicrobial potency and provide the foundation for future use of this new class of synthetic glycopeptide analogues.
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Affiliation(s)
- Maxwell J. Moore
- Department of Chemistry and The Skaggs Institute for Chemical Biology, The Scripps Research Institute, 10550 N. Torrey Pines Road, La Jolla, CA 92037, USA
| | - Pengjin Qin
- Department of Chemistry and The Skaggs Institute for Chemical Biology, The Scripps Research Institute, 10550 N. Torrey Pines Road, La Jolla, CA 92037, USA
| | - Naoto Yamasaki
- Department of Chemistry and The Skaggs Institute for Chemical Biology, The Scripps Research Institute, 10550 N. Torrey Pines Road, La Jolla, CA 92037, USA
| | - Xianhuang Zeng
- Department of Chemistry and The Skaggs Institute for Chemical Biology, The Scripps Research Institute, 10550 N. Torrey Pines Road, La Jolla, CA 92037, USA
| | - D. Jamin Keith
- Department of Chemistry and The Skaggs Institute for Chemical Biology, The Scripps Research Institute, 10550 N. Torrey Pines Road, La Jolla, CA 92037, USA
| | - Sunna Jung
- Department of Chemistry and The Skaggs Institute for Chemical Biology, The Scripps Research Institute, 10550 N. Torrey Pines Road, La Jolla, CA 92037, USA
| | - Takumi Fukazawa
- Department of Chemistry and The Skaggs Institute for Chemical Biology, The Scripps Research Institute, 10550 N. Torrey Pines Road, La Jolla, CA 92037, USA
| | - Katherine Graham-O’Regan
- Department of Chemistry and The Skaggs Institute for Chemical Biology, The Scripps Research Institute, 10550 N. Torrey Pines Road, La Jolla, CA 92037, USA
| | - Zhi-Chen Wu
- Department of Chemistry and The Skaggs Institute for Chemical Biology, The Scripps Research Institute, 10550 N. Torrey Pines Road, La Jolla, CA 92037, USA
| | - Shreyosree Chatterjee
- Department of Chemistry and The Skaggs Institute for Chemical Biology, The Scripps Research Institute, 10550 N. Torrey Pines Road, La Jolla, CA 92037, USA
| | - Dale L. Boger
- Department of Chemistry and The Skaggs Institute for Chemical Biology, The Scripps Research Institute, 10550 N. Torrey Pines Road, La Jolla, CA 92037, USA
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Moore MJ, Qin P, Keith DJ, Wu ZC, Jung S, Chatterjee S, Tan C, Qu S, Cai Y, Stanfield RL, Boger DL. Divergent Total Synthesis and Characterization of Maxamycins. J Am Chem Soc 2023. [PMID: 37278486 DOI: 10.1021/jacs.3c03710] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
A new streamlined and scaled divergent total synthesis of pocket-modified vancomycin analogs is detailed that provides a common late-stage intermediate [Ψ[C(═S)NH]Tpg4]vancomycin (LLS = 18 steps, 12% overall yield, >5 g prepared) to access both existing and future pocket modifications. Highlights of the approach include an atroposelective synthesis of [Ψ[C(═S)NH]Tpg4]vancomycin aglycon (11), a one-pot enzymatic glycosylation for direct conversion to [Ψ[C(═S)NH]Tpg4]vancomycin (12), and new powerful methods for the late-stage conversion of the embedded thioamide to amidine/aminomethylene pocket modifications. Incorporation of two peripheral modifications provides a scalable total synthesis of the maxamycins, all prepared from aglycon 11 without use of protecting groups. Thus, both existing and presently unexplored pocket-modified analogues paired with a range of peripheral modifications are accessible from this common thioamide intermediate. In addition to providing an improved synthesis of the initial member of the maxamycins, this is illustrated herein with the first synthesis and examination of maxamycins that contain the most effective of the pocket modifications (amidine) described to date combined with two additional peripheral modifications. These new amidine-based maxamycins proved to be potent, durable, and efficacious antimicrobial agents that display equipotent activity against vancomycin-sensitive and vancomycin-resistant Gram-positive organisms and act by three independent synergistic mechanisms of action. In the first such study conducted to date, one new maxamycin (21, MX-4) exhibited efficacious in vivo activity against a feared and especially challenging multidrug-resistant (MRSA) and vancomycin-resistant (VRSA) S. aureus bacterial strain (VanA VRS-2) for which vancomycin is inactive.
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Moore MJ, Qin P, Keith DJ, Boger DL. Improved preparative enzymatic glycosylation of vancomycin aglycon and analogues. Tetrahedron 2023; 131:133211. [PMID: 36776940 PMCID: PMC9913888 DOI: 10.1016/j.tet.2022.133211] [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] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Modifications to the enzymatic glycosylation of vancomycin and its residue 4 thioamide analogue are detailed that significantly reduce the enzyme loading and amount of glycosyl donor needed for each glycosylation reaction, provide a streamlined synthesis and replacement for the synthetic UDP-vancosamine glycosyl donor to improve both access and storage stability, and permit a single-pot, two-step conversion of the aglycons to the fully glycosylated synthetic glycopeptides now conducted at higher concentrations. The improvements are exemplified with the two-step, one-pot glycosylation of [Ψ[C(=S)NH]Tpg4]vancomycin aglycon (92%) conducted on a 400 mg scale (2 mg to 1 g scales) and vancomycin aglycon itself (5 mg scale, 84%).
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Affiliation(s)
- Maxwell J. Moore
- Department of Chemistry and Skaggs Institute for Chemical Biology, The Scripps Research Institute, 10550 N. Torrey Pines Road, La Jolla, California 92037, USA
| | - Pengjin Qin
- Department of Chemistry and Skaggs Institute for Chemical Biology, The Scripps Research Institute, 10550 N. Torrey Pines Road, La Jolla, California 92037, USA
| | - D. Jamin Keith
- Department of Chemistry and Skaggs Institute for Chemical Biology, The Scripps Research Institute, 10550 N. Torrey Pines Road, La Jolla, California 92037, USA
| | - Dale L. Boger
- Department of Chemistry and Skaggs Institute for Chemical Biology, The Scripps Research Institute, 10550 N. Torrey Pines Road, La Jolla, California 92037, USA
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Abstract
A next-generation total synthesis of vancomycin aglycon is detailed that was achieved in 17 steps (longest linear sequence, LLS) from the constituent amino acid subunits with kinetically controlled diastereoselective introduction of all three elements of atropisomerism. In addition to new syntheses of three of the seven amino acid subunits, highlights of the approach include a ligand-controlled atroposelective one-pot Miyaura borylation-Suzuki coupling sequence for introduction of the AB biaryl axis of chirality (>20:1 dr), an essentially instantaneous and scalable macrolactamization of the AB ring system nearly free of competitive epimerization (>30:1 dr), and two room-temperature atroposelective intramolecular SNAr cyclizations for sequential CD (8:1 dr) and DE ring closures (14:1 dr) that benefit from both preorganization by the preformed AB ring system and subtle substituent effects. Combined with a protecting group free two-step enzymatic glycosylation of vancomycin aglycon, this provides a 19-step total synthesis of vancomycin. The approach paves the way for large-scale synthetic preparation of pocket-modified vancomycin analogues that directly address the underlying mechanism of resistance to vancomycin.
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Affiliation(s)
- Maxwell J Moore
- Department of Chemistry and Skaggs Institute for Chemical Biology, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037, United States
| | - Shiwei Qu
- Department of Chemistry and Skaggs Institute for Chemical Biology, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037, United States
| | - Ceheng Tan
- Department of Chemistry and Skaggs Institute for Chemical Biology, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037, United States
| | - Yu Cai
- Department of Chemistry and Skaggs Institute for Chemical Biology, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037, United States
| | - Yuzo Mogi
- Department of Chemistry and Skaggs Institute for Chemical Biology, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037, United States
| | - D Jamin Keith
- Department of Chemistry and Skaggs Institute for Chemical Biology, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037, United States
| | - Dale L Boger
- Department of Chemistry and Skaggs Institute for Chemical Biology, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037, United States
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Abstract
Phosphocholine is a small haptenic molecule that is both a precursor and degradation product of choline. Phosphocholine decorates a number of biologics such as lipids and oligosaccharides. In this study, an air and bench stable phosphocholine donor has been developed and evaluated with a number of alcohol acceptors. Using a one-pot, three-step sequence, (phosphitylation, oxidation, and phosphate deprotection) phosphocholine derivatives are synthesized in high yields. Of particular interest is the synthesis of miltefosine, the lone oral drug approved to treat leishmaniasis. Due to its prohibitive expense ($1500 per g), miltefosine is not accesable for the majority of the world's patients. Based on the described reaction sequence, this drug can be produced for $25 per g.
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Affiliation(s)
- Lianyan L Xu
- Department of Chemistry, Vanderbilt University, Nashville, TN 37235, USA.
| | - Lawrence J Berg
- Department of Chemistry, Vanderbilt University, Nashville, TN 37235, USA.
| | - D Jamin Keith
- Department of Chemistry, Vanderbilt University, Nashville, TN 37235, USA.
| | - Steven D Townsend
- Department of Chemistry, Vanderbilt University, Nashville, TN 37235, USA.
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Keith DJ, Townsend SD. Total Synthesis of the Congested, Bisphosphorylated Morganella morganii Zwitterionic Trisaccharide Repeating Unit. J Am Chem Soc 2019; 141:12939-12945. [PMID: 31329445 DOI: 10.1021/jacs.9b06830] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Zwitterionic polysaccharides (ZPSs) activate T-cell-dependent immune responses by major histocompatibility complex class II presentation. Herein, we report the first synthesis of a Morganella morganii ZPS repeating unit as an enabling tool in the synthesis of novel ZPS materials. The repeating unit incorporates a 1,2-cis-α-glycosidic bond; the problematic 1,2-trans-galactosidic bond, Gal-β-(1 → 3)-GalNAc; and phosphoglycerol and phosphocholine residues which have not been previously observed together as functional groups on the same oligosaccharide. The successful third-generation approach leverages a first in class glycosylation of a phosphoglycerol-functionalized acceptor. To install the phosphocholine unit, a highly effective phosphocholine donor was synthesized.
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Affiliation(s)
- D Jamin Keith
- Department of Chemistry , Vanderbilt University , Nashville , Tennessee 37235 , United States
| | - Steven D Townsend
- Department of Chemistry , Vanderbilt University , Nashville , Tennessee 37235 , United States
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Keith DJ, Marasligiller SA, Sasse AW, Townsend SD. One-pot Microwave-assisted Conversion of Anomeric Nitrate-esters to Trichloroacetimidates. J Vis Exp 2018. [PMID: 29364227 DOI: 10.3791/56610] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
The goal of the following procedure is to provide a demonstration of the one-pot conversion of a 2-azido-1-nitrate-ester to a trichloroacetimidate glycosyl donor. Following azido-nitration of a glycal, the product 2-azido-1-nitrate ester can be hydrolyzed under microwave-assisted irradiation. This transformation is usually achieved using strongly nucleophilic reagents and extended reaction times. Microwave irradiation induces hydrolysis, in the absence of reagents, with short reaction times. Following denitration, the intermediate anomeric alcohol is converted, in the same pot, to the corresponding 2-azido-1-trichloroacetimidate.
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Affiliation(s)
| | | | | | - Steven D Townsend
- Department of Chemistry, Vanderbilt University; Institute of Chemical-Biology, Vanderbilt University;
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Keith DJ, Townsend SD. Direct, microwave-assisted substitution of anomeric nitrate-esters. Carbohydr Res 2017; 442:20-24. [DOI: 10.1016/j.carres.2017.02.005] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2017] [Revised: 02/21/2017] [Accepted: 02/21/2017] [Indexed: 11/28/2022]
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Keith DJ, Jones T, Ives A, de Berker D, Verne J. Rate of positive diagnosis of skin cancer and its stage in two-week wait referrals in England according to age. Clin Exp Dermatol 2017; 42:145-152. [PMID: 28044351 DOI: 10.1111/ced.12989] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/13/2016] [Indexed: 12/01/2022]
Abstract
BACKGROUND The incidence of skin cancer is increasing. The two-week wait conversion rate (TWWCR) is the percentage of urgent suspected skin cancer referrals that are confirmed as cancer. AIMS To examine the relationships between different epidemiological factors and TWWCR for malignant melanoma (MM) and cutaneous squamous cell carcinoma (SCC). METHODS We extracted data from the National Cancer Data Repository (NCDR) and National Cancer Waiting Times Monitoring Dataset between 2009 and 2010 for MM and SCC in England. We conducted partial correlation and stepwise multiple regression analysis on TWWCR, age, incidence, detection rate, tumour thickness (MM only), percentage MM/SCC and social deprivation. We also looked at the two-week wait referral rate (TWWRR) and incidence rate with respect to age. RESULTS TWWCR was significantly correlated with age when partial correlation was used to control for the factors described above for MM (P < 0.05) and SCC (P < 0.001). Stepwise regression of these factors returned only age as significant in the final model for MM (P < 0.001) and SCC (P < 0.01). Incidence of MM and SCC increased with age. TWWRR also increase with age, but with higher rate in younger people relative to their incidence. CONCLUSIONS Age is a predictor of TWWCR independent of the other factors measured, including thickness and incidence. This may be explained by the higher number of referrals for younger patients despite the lower incidence of skin cancer in this group. This may reflect a more appropriate rate of referral in order to achieve earlier diagnosis and better outcomes.
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Affiliation(s)
- D J Keith
- University Hospitals Bristol NHS Foundation Trust, Bristol, UK
| | - T Jones
- Public Health England-South West, Bristol, UK
| | - A Ives
- Public Health England-South West, Bristol, UK
| | - D de Berker
- University Hospitals Bristol NHS Foundation Trust, Bristol, UK
| | - J Verne
- Public Health England-South West, Bristol, UK
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Sarma VS, Howlader M, Nusrath MA, Keith DJ. Retrobulbar haemorrhage: improved visual acuity after delayed surgical decompression. Br J Hosp Med (Lond) 2015; 76:722-3. [PMID: 26646337 DOI: 10.12968/hmed.2015.76.12.722] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- V S Sarma
- Dental Student in the School of Dental Sciences, Newcastle University, Newcastle upon Tyne NE2 4BW
| | - M Howlader
- GP Specialty Trainee in the Postgraduate School of Primary Care, Northern Deanery, Newcastle upon Tyne
| | - M A Nusrath
- Consultant in the Department of Oral and Maxillofacial Surgery, Nottingham University Hospitals NHS Trust, Nottingham
| | - D J Keith
- Consultant in the Department of Oral and Maxillofacial Surgery, Sunderland Royal Hospital, Sunderland
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Sharpe AG, Parkin IA, Keith DJ, Lydiate DJ. Frequent nonreciprocal translocations in the amphidiploid genome of oilseed rape (Brassica napus). Genome 2012; 38:1112-21. [PMID: 18470235 DOI: 10.1139/g95-148] [Citation(s) in RCA: 176] [Impact Index Per Article: 14.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
A RFLP map of Brassica napus, consisting of 277 loci arranged in 19 linkage groups, was produced from genetic segregation in a combined population of 174 doubled-haploid microspore-derived lines. The integration of this map with a B. napus map derived from a resynthesized B. napus x oilseed rape cross allowed the 10 linkage groups of the B. napus A genome and the 9 linkage groups of the C genome to be identified. Collinear patterns of marker loci on different linkage groups suggested potential partial homoeologues. RFLP patterns consistent with aberrant chromosomes were observed in 9 of the 174 doubled-haploid lines. At least 4 of these lines carried nonreciprocal, homoeologous translocations. These translocations were probably the result of homoeologous recombination in the amphidiploid genome of oilseed rape, suggesting that domesticated B. napus is unable to control chromosome pairing completely. Evidence for genome homogenization in oilseed rape is presented and its implications on genetic mapping in amphidiploid species is discussed. The level of polymorphism in the A genome was higher than that in the C genome and this might be a general property of oilseed rape crosses.
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Parkin IA, Sharpe AG, Keith DJ, Lydiate DJ. Identification of the A and C genomes of amphidiploid Brassica napus (oilseed rape). Genome 2012; 38:1122-31. [PMID: 18470236 DOI: 10.1139/g95-149] [Citation(s) in RCA: 280] [Impact Index Per Article: 23.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
A genetic linkage map consisting of 399 RFLP-defined loci was generated from a cross between resynthesized Brassica napus (an interspecific B. rapa x B. oleracea hybrid) and "natural" oilseed rape. The majority of loci exhibited disomic inheritance of parental alleles demonstrating that B. rapa chromosomes were each pairing exclusively with recognisable A-genome homologues in B. napus and that B. oleracea chromosomes were pairing similarly with C-genome homologues. This behaviour identified the 10 A genome and 9 C genome linkage groups of B. napus and demonstrated that the nuclear genomes of B. napus, B. rapa, and B. oleracea have remained essentially unaltered since the formation of the amphidiploid species, B. napus. A range of unusual marker patterns, which could be explained by aneuploidy and nonreciprocal translocations, were observed in the mapping population. These chromosome abnormalities were probably caused by associations between homoeologous chromosomes at meiosis in the resynthesized parent and the F1 plant leading to nondisjunction and homoeologous recombination.
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Nobre J, Keith DJ, Dunwell JM. Morphogenesis and regeneration from stomatal guard cell complexes of cotton (Gossypium hirsutum L.). Plant Cell Rep 2001; 20:8-15. [PMID: 30759918 DOI: 10.1007/s002990000281] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
The development of a regeneration system from cotton stomatal guard cells directly on epidermal strips is described. The most important factors affecting embryogenic callus initiation in both of the varieties tested (Coker 312 and 315) were the source of the epidermal tissue, including plant age (4-5 months old), the developmental stage of the flower (opening flower stage) from which bracts were obtained, the composition of the culture medium and light irradiance. The flower developmental stage was critical for callus formation, which was observed only from bracts obtained from opening flowers. In addition, epidermal strips excised from the bract basal region were more responsive in culture than those obtained from the top region. Improved callus initiation was obtained on epidermal strips which had their cuticle in contact with the culture medium. Light irradiance was a limiting factor for embryogenic callus formation, which was observed only in calluses cultured under the lower light irradiance (15.8 μmol m-2 s-1). Somatic embryogenesis was observed on callus cultures subcultured consecutively to a culture medium containing naphthalene acetic acid (10.7 μM) and isopentenyladenine (4.9 μM). Histodifferentiation of somatic embryos was improved on a medium containing naphthaleneacetic acid (8.1 μM)+isopentenyladenine (2.5 μM) and abscisic acid (0.19-0.38 μM). Somatic embryo germination and plantlet development were obtained using established protocols with few modifications. On average, one fully developed plant was obtained from the culture of circa 100 epidermal strips in both cultivars.
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Affiliation(s)
- J Nobre
- School of Plant Sciences, The University of Reading, Whiteknights, P.O. Box 221, Reading RG6 6AS, UK e-mail: Fax: +44-118-9316577, , , , , , GB
| | - D J Keith
- Zeneca Agrochemicals, Jealott's Hill Research Station, Bracknell, RG42 6ET, UK, , , , , , GB
| | - J M Dunwell
- School of Plant Sciences, The University of Reading, Whiteknights, P.O. Box 221, Reading RG6 6AS, UK e-mail: Fax: +44-118-9316577, , , , , , GB
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Kaplan GB, Leite-Morris KA, Keith DJ. Differential effects of treatment with typical and atypical antipsychotic drugs on adenylyl cyclase and G proteins. Neurosci Lett 1999; 273:147-50. [PMID: 10515180 DOI: 10.1016/s0304-3940(99)00610-2] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [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: 11/18/2022]
Abstract
We examined the effects of chronic in vivo antipsychotic drug treatments on G protein function and regulation. Mice were treated with typical antipsychotic haloperidol (6 mg/kg per day) and atypical agent olanzapine (20 mg/kg per day) for 14 days via mini-osmotic pumps. G protein-activated adenylyl cyclase activity in brain tissues was measured in the presence of guanine nucleotide analogue guanosine-5'-O(3-thiotriphosphate) tetralithium salt, or GTPgammaS. In frontal cortex, haloperidol treatment produced 21% increases in the GTPgammaS -mediated adenylyl cyclase Emax value (vs. vehicle controls) while olanzapine produced 20% reductions in this value (vs. controls); these effects were significant. In striatum, olanzapine treatment produced significant 31 and 27% decreases in Emax values compared with vehicle and haloperidol treatment, respectively. Chronic haloperidol treatment produced significant 24% reductions in the immunoreactivity of cortical, but not striatal, Gialpha1,2 subunits. There were no effects of chronic olanzapine treatment on G(i)alpha1,2 levels and no effects of either antipsychotic on G(s)alpha, levels. Chronic haloperidol and olanzapine treatments differentially regulate G protein-mediated adenylyl cyclase responses in brain regions possibly relating to their unique effects on G protein-coupled receptors.
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Affiliation(s)
- G B Kaplan
- Mental Health and Behavioral Sciences Service, Veterans Affairs Medical Center, Providence, RI 02908, USA.
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Bohuon EJ, Keith DJ, Parkin IA, Sharpe AG, Lydiate DJ. Alignment of the conserved C genomes of Brassica oleracea and Brassica napus. Theor Appl Genet 1996; 93:833-9. [PMID: 24162415 DOI: 10.1007/bf00224083] [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] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/02/1995] [Accepted: 05/31/1996] [Indexed: 05/09/2023]
Abstract
A population of 169 microspore-derived doubled-haploid lines was produced from a highly polymorphic Brassica oleracea cross. A dense genetic linkage map of B. oleracea was then developed based on the segregation of 303 RFLP-defined loci. It is hoped that these lines will be used by other geneticists to facilitate the construction of a unified genetic map of B. oleracea. When the B. oleracea map was compared to one ofB. napus (Parkin et al. 1995), based on the same RFLP probes (Sharpe et al. 1995), good collinearity between the C-genome linkage groups of the two species was observed.
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Affiliation(s)
- E J Bohuon
- Brassica and Oilseeds Research Department, John Innes Centre, Colney Lane, NR4 7UH, Norwich, UK
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O'Barr TP, Keith DJ, Blair EB. An evaluation of the fluorometric determination of isonicotinic acid hydrazide. Am Rev Respir Dis 1973; 107:472-4. [PMID: 4690496 DOI: 10.1164/arrd.1973.107.3.472] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
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