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Douglass N, Omar R, Munyanduki H, Suzuki A, de Moor W, Mutowembwa P, Pretorius A, Nefefe T, van Schalkwyk A, Kara P, Heath L, Williamson AL. The Development of Dual Vaccines against Lumpy Skin Disease (LSD) and Bovine Ephemeral Fever (BEF). Vaccines (Basel) 2021; 9:vaccines9111215. [PMID: 34835146 PMCID: PMC8621795 DOI: 10.3390/vaccines9111215] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2021] [Revised: 10/11/2021] [Accepted: 10/14/2021] [Indexed: 12/21/2022] Open
Abstract
Dual vaccines (n = 6) against both lumpy skin disease (LSD) and bovine ephemeral fever (BEF) were constructed, based on the BEFV glycoprotein (G) gene, with or without the BEFV matrix (M) protein gene, inserted into one of two different LSDV backbones, nLSDV∆SOD-UCT or nLSDVSODis-UCT. The inserted gene cassettes were confirmed by PCR; and BEFV protein was shown to be expressed by immunofluorescence. The candidate dual vaccines were initially tested in a rabbit model; neutralization assays using the South African BEFV vaccine (B-Phemeral) strain showed an African consensus G protein gene (Gb) to give superior neutralization compared to the Australian (Ga) gene. The two LSDV backbones expressing both Gb and M BEFV genes were tested in cattle and shown to elicit neutralizing responses to LSDV as well as BEFV after two inoculations 4 weeks apart. The vaccines were safe in cattle and all vaccinated animals were protected against virulent LSDV challenge, unlike a group of control naïve animals, which developed clinical LSD. Both neutralizing and T cell responses to LSDV were stimulated upon challenge. After two inoculations, all vaccinated animals produced BEFV neutralizing antibodies ≥ 1/20, which is considered protective for BEF.
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Affiliation(s)
- Nicola Douglass
- Division of Medical Virology, Department of Pathology, Faculty of Health Sciences, University of Cape Town, Cape Town 7925, South Africa; (R.O.); (H.M.); (A.S.); (W.d.M.); (A.-L.W.)
- Institute of Infectious Disease and Molecular Medicine, University of Cape Town, Cape Town 7925, South Africa
- Correspondence: ; Tel.: +27-832-310-553
| | - Ruzaiq Omar
- Division of Medical Virology, Department of Pathology, Faculty of Health Sciences, University of Cape Town, Cape Town 7925, South Africa; (R.O.); (H.M.); (A.S.); (W.d.M.); (A.-L.W.)
- Institute of Infectious Disease and Molecular Medicine, University of Cape Town, Cape Town 7925, South Africa
| | - Henry Munyanduki
- Division of Medical Virology, Department of Pathology, Faculty of Health Sciences, University of Cape Town, Cape Town 7925, South Africa; (R.O.); (H.M.); (A.S.); (W.d.M.); (A.-L.W.)
- Institute of Infectious Disease and Molecular Medicine, University of Cape Town, Cape Town 7925, South Africa
| | - Akiko Suzuki
- Division of Medical Virology, Department of Pathology, Faculty of Health Sciences, University of Cape Town, Cape Town 7925, South Africa; (R.O.); (H.M.); (A.S.); (W.d.M.); (A.-L.W.)
- Institute of Infectious Disease and Molecular Medicine, University of Cape Town, Cape Town 7925, South Africa
| | - Warren de Moor
- Division of Medical Virology, Department of Pathology, Faculty of Health Sciences, University of Cape Town, Cape Town 7925, South Africa; (R.O.); (H.M.); (A.S.); (W.d.M.); (A.-L.W.)
- Institute of Infectious Disease and Molecular Medicine, University of Cape Town, Cape Town 7925, South Africa
| | - Paidamwoyo Mutowembwa
- Onderstepoort Veterinary Institute, ARC, Pretoria 0110, South Africa; (P.M.); (A.P.); (T.N.); (A.v.S.); (P.K.); (L.H.)
| | - Alri Pretorius
- Onderstepoort Veterinary Institute, ARC, Pretoria 0110, South Africa; (P.M.); (A.P.); (T.N.); (A.v.S.); (P.K.); (L.H.)
| | - Tshifhiwa Nefefe
- Onderstepoort Veterinary Institute, ARC, Pretoria 0110, South Africa; (P.M.); (A.P.); (T.N.); (A.v.S.); (P.K.); (L.H.)
| | - Antoinette van Schalkwyk
- Onderstepoort Veterinary Institute, ARC, Pretoria 0110, South Africa; (P.M.); (A.P.); (T.N.); (A.v.S.); (P.K.); (L.H.)
| | - Pravesh Kara
- Onderstepoort Veterinary Institute, ARC, Pretoria 0110, South Africa; (P.M.); (A.P.); (T.N.); (A.v.S.); (P.K.); (L.H.)
| | - Livio Heath
- Onderstepoort Veterinary Institute, ARC, Pretoria 0110, South Africa; (P.M.); (A.P.); (T.N.); (A.v.S.); (P.K.); (L.H.)
| | - Anna-Lise Williamson
- Division of Medical Virology, Department of Pathology, Faculty of Health Sciences, University of Cape Town, Cape Town 7925, South Africa; (R.O.); (H.M.); (A.S.); (W.d.M.); (A.-L.W.)
- Institute of Infectious Disease and Molecular Medicine, University of Cape Town, Cape Town 7925, South Africa
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Upfold N, Ross C, Bishop ÖT, Luke GA, Knox C. The generation and characterisation of neutralising antibodies against the Theiler’s murine encephalomyelitis virus (TMEV) GDVII capsid reveals the potential binding site of the host cell co-receptor, heparan sulfate. Virus Res 2018; 244:153-163. [DOI: 10.1016/j.virusres.2017.11.017] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2017] [Revised: 11/09/2017] [Accepted: 11/15/2017] [Indexed: 11/26/2022]
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Storbeck KH, Swart AC, Lombard N, Adriaanse CV, Swart P. Cytochrome b(5) forms homomeric complexes in living cells. J Steroid Biochem Mol Biol 2012; 132:311-21. [PMID: 22878120 DOI: 10.1016/j.jsbmb.2012.07.006] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/04/2012] [Revised: 07/23/2012] [Accepted: 07/25/2012] [Indexed: 11/24/2022]
Abstract
Cytochrome b(5) (cyt-b(5)) is a ubiquitous hemoprotein also associated with microsomal cytochrome P450 17α-hydroxylase/17,20 lyase (CYP17A1). In the steroidogenic pathway CYP17A1 catalyses the metabolism of pregnenolone, yielding both glucocorticoid and androgen precursors. While not affecting the 17α-hydroxylation of pregnenolone, cyt-b(5) augments the 17,20 lyase reaction of 17-hydroxypregnenolone, catalyzing the formation of DHEA, through direct protein-protein interactions. In this study, multimeric complex formation of cyt-b(5) and the possible regulatory role of these complexes were investigated. Cyt-b(5) was isolated from ovine liver and used to raise anti-sheep cyt-b(5) immunoglobulins. Immunochemical studies revealed that, in vivo, cyt-b(5) is primarily found in the tetrameric form. Subsequent fluorescent resonance energy transfer (FRET) studies in COS-1 cells confirmed the formation of homomeric complexes by cyt-b(5) in live cells. Site-directed mutagenesis revealed that the C-terminal linker domain of cyt-b(5) is vital for complex formation. The 17,20-lyase activity of CYP17 was augmented by truncated cyt-b(5), which is unable to form complexes when co-expressed in COS-1 cells, thereby implicating the monomeric form of cyt-b(5) as the active species. This study has shown for the first time that cyt-b(5) forms homomeric complexes in vivo, implicating complex formation as a possible regulatory mechanism in steroidogenesis.
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Affiliation(s)
- Karl-Heinz Storbeck
- Department of Biochemistry, University of Stellenbosch, Stellenbosch 7600, South Africa
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Chirwa N, Govender D, Ndimba B, Lotz Z, Tyler M, Panieri E, Kahn D, Mall AS. A 40-50kDa Glycoprotein Associated with Mucus is Identified as α-1-Acid Glycoprotein in Carcinoma of the Stomach. J Cancer 2012; 3:83-92. [PMID: 22359529 PMCID: PMC3283834 DOI: 10.7150/jca.3737] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2011] [Accepted: 12/05/2012] [Indexed: 12/23/2022] Open
Abstract
Background and Aim: Secreted gastric mucins are large O-glycosylated proteins of crude mucus gels which are aberrantly expressed in malignancy. An albumin associated 55-65kDa glycoprotein was previously shown in mucus gels in gastric cancer. The aim of this study was to investigate its expression and identification in human gastric tissue. Methods: Mucins were purified from crude mucus scrapings of 16 partial and 11 total resections and a rabbit polyclonal antibody was raised to the 55-65kDa glycoprotein. The location and expression of the glycoprotein was examined in normal gastric mucosa (n=20), intestinal metaplasia (n=18) and gastric cancer (n=27) tissue by immunohistochemistry. Mucins were analyzed by isoelectric focusing (IEF) on 2-D polyacrylamide gels. Identification of the 40-50kDa glycoprotein was by MALDI-TOF MS technique. Plasma levels were examined by Western blotting. Results: Extensive SDS-PAGE analysis gave a PAS positive glycoprotein in the 40-50kDa range, in patients with gastric cancer but not normals. It was expressed in parietal and columnar cells of normal gastric tissue and intestinal metaplasia respectively, and in 22 of 27 gastric cancer specimens. In 2-D PAGE stained with Coomassie Blue there were 3 spots positively identified as alpha-1-acid glycoprotein (AGP) by MALDI-TOF MS technique. PAS staining revealed a single bright spot in the same position but could not be identified. Preliminary measurements showed slightly higher levels of AGP in plasma of patients with gastric carcinoma. Conclusion: AGP levels are increased in gastric tissue and in the plasma of those with carcinoma of the stomach.
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Affiliation(s)
- Nthato Chirwa
- 1. Department of Surgery, University of Cape Town, South Africa
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Mbita Z, Meyer M, Skepu A, Hosie M, Rees J, Dlamini Z. De-regulation of the RBBP6 isoform 3/DWNN in human cancers. Mol Cell Biochem 2011; 362:249-62. [PMID: 22139301 DOI: 10.1007/s11010-011-1150-5] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2011] [Accepted: 11/03/2011] [Indexed: 01/30/2023]
Abstract
Retinoblastoma binding protein 6 (RBBP6) is a nuclear protein, previously implicated in the regulation of cell cycle and apoptosis. The human RBBP6 gene codes for three protein isoforms and isoform 3 consists of the domain with no name domain only whilst the other two isoforms, 1 and 2 comprise of additional zinc, RING, retinoblastoma and p53 binding domains. In this study, the localization of RBBP6 using RBBP6 variant 3 mRNA-specific probe was performed to investigate the expression levels of the gene in different tumours and find a link between RBBP6 and human carcinogenesis. Using FISH, real-time PCR and Western blotting analysis our results show that RBBP6 isoform 3 is down-regulated in human cancers. RBBP6 isoform 3 knock-down resulted in reduced G2/M cell cycle arrest whilst its over-expression resulted in increased G2/M cell cycle arrest using propidium iodide DNA staining. The results further demonstrate that the RBBP6 isoform 3 may be the cell cycle regulator and involved in mitotic apoptosis not the isoform 1 as previously reported for mice. In conclusion, these findings suggest that RBBP6 isoform 3 is a cell cycle regulator and may be de-regulated in carcinogenesis.
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Affiliation(s)
- Zukile Mbita
- College of Agriculture and Environmental Science, University of South Africa, Florida Campus, Johannesburg, South Africa
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6
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Louw CA, Ludewig MH, Blatch GL. Overproduction, purification and characterisation of Tbj1, a novel Type III Hsp40 from Trypanosoma brucei, the African sleeping sickness parasite. Protein Expr Purif 2009; 69:168-77. [PMID: 19815073 DOI: 10.1016/j.pep.2009.09.023] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2009] [Revised: 09/27/2009] [Accepted: 09/29/2009] [Indexed: 11/24/2022]
Abstract
The heat shock protein 40 (Hsp40) family of proteins act as co-chaperones of the heat shock protein 70 (Hsp70) chaperone family, and together they play a vital role in the maintenance of cellular homeostasis. The Type III class of Hsp40s are diverse in terms of both sequence identity and function and have not been extensively characterised. The Trypanosoma brucei parasite is the causative agent of Human African Trypanosomiasis, and possesses an unusually large Hsp40 complement, consisting mostly of Type III Hsp40s. A novel T. brucei Type III Hsp40, Tbj1, was heterologously expressed, purified, and found to exist as a compact monomer in solution. Using polyclonal antibodies to the full-length recombinant protein, Tbj1 was found by Western analysis to be expressed in the T. brucei bloodstream-form. Tbj1 was found to be able to assist two different Hsp70 proteins in the suppression of protein aggregation in vitro, despite being unable to stimulate their ATPase activity. This indicated that while Tbj1 did not possess independent chaperone activity, it potentially functioned as a novel co-chaperone of Hsp70 in T. brucei.
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Affiliation(s)
- Cassandra A Louw
- Biomedical Biotechnology Research Unit, Department of Biochemistry, Microbiology and Biotechnology, Rhodes University, Grahamstown 6140, South Africa
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Bellstedt DU. Enzyme-linked immunosorbent assay detection of Ralstonia solanacearum in potatoes: the South African experience. METHODS IN MOLECULAR BIOLOGY (CLIFTON, N.J.) 2009; 508:51-62. [PMID: 19301746 DOI: 10.1007/978-1-59745-062-1_5] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Outbreaks of bacterial wilt caused by Ralstonia solanacearum in South Africa in the 1980s necessitated the development of a sensitive assay for its detection. In this chapter, the development of an enzyme-linked immunosorbent assay (ELISA) for the detection of Ralstonia solanacearum including antibody production, the ELISA method itself, potato sample preparation for testing, ELISA result validation and interpretation, and confirmation of infection are discussed. Data showing the drop in the Ralstonia solanacearum infection rate, after testing was implemented, are presented and shows how the use of this method has brought the disease under control in South Africa.
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Gundllapalli SB, Pretorius IS, Cordero Otero RR. Effect of the cellulose-binding domain on the catalytic activity of a β-glucosidase from Saccharomycopsis fibuligera. J Ind Microbiol Biotechnol 2007; 34:413-21. [PMID: 17333092 DOI: 10.1007/s10295-007-0213-9] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2005] [Accepted: 02/04/2007] [Indexed: 10/23/2022]
Abstract
Enzyme engineering was performed to link the beta-glucosidase enzyme (BGL1) from Saccharomycopsis fibuligera to the cellulose-binding domain (CBD2) of Trichoderma reesei cellobiohydrolase (CBHII) to investigate the effect of a fungal CBD on the enzymatic characteristics of this non-cellulolytic yeast enzyme. Recombinant enzymes were constructed with single and double copies of CBD2 fused at the N-terminus of BGL1 to mimic the two-domain organization displayed by cellulolytic enzymes in nature. The engineered S. fibuligera beta-glucosidases were expressed in Saccharomyces cerevisiae under the control of phosphoglycerate-kinase-1 promoter (PGK1 ( P )) and terminator (PGK1 ( T )) and yeast mating pheromone alpha-factor secretion signal (MFalpha1 ( S )). The secreted enzymes were purified and characterized using a range of cellulosic and non-cellulosic substrates to illustrate the effect of the CBD on their enzymatic activity. The results indicated that the recombinant enzymes of BGL1 displayed a 2-4-fold increase in their hydrolytic activity toward cellulosic substrates like avicel, amorphous cellulose, bacterial microcrystalline cellulose, and carboxy methyl cellulose in comparison with the native enzyme. The organization of the CBD in these recombinant enzymes also resulted in enhanced substrate affinity, molecular flexibility and synergistic activity, thereby improving the ability of the enzymes to act on and hydrolyze cellulosic substrates, as characterized by adsorption, kinetics, thermal stability, and scanning electron microscopic analyses.
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Affiliation(s)
- Sarath B Gundllapalli
- Institute for Wine Biotechnology, Department of Viticulture and Oenology, Stellenbosch University, Victoria Street, Stellenbosch, ZA, 7602, South Africa
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Development of a screening method for the indentification of a novelSaccharomyces cerevisiae mutant over-expressingTrichoderma reesei cellobiohydrolase II. ANN MICROBIOL 2006. [DOI: 10.1007/bf03174996] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022] Open
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11
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Edward V, Pillay V, Swart P, Singh S. Localisation of Thermomyces lanuginosus SSBP xylanase on polysulphone membranes using immunogold labelling and environmental scanning electron microscopy (ESEM). Process Biochem 2003. [DOI: 10.1016/s0032-9592(02)00206-6] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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12
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Swart P, Lombard N, Swart AC, van der Merwe T, Murry BA, Nicol M, Ian Mason J. Ovine steroid 17alpha-hydroxylase cytochrome P450: characteristics of the hydroxylase and lyase activities of the adrenal cortex enzyme. Arch Biochem Biophys 2003; 409:145-52. [PMID: 12464253 DOI: 10.1016/s0003-9861(02)00547-7] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
The steroid 17-hydroxylase cytochrome P450 (CYP17) found in mammalian adrenal and gonadal tissues typically exhibits not only steroid 17-hydroxylase activity but also C-17,20-lyase activity. These two reactions, catalyzed by CYP17, allow for the biosynthesis of the glucocorticoids in the adrenal cortex, as a result of the 17-hydroxylase activity, and for the biosynthesis of androgenic C(19) steroids in the adrenal cortex and gonads as a result of the additional lyase activity. A major difference between species with regard to adrenal steroidogenesis resides in the lyase activity of CYP17 toward the hydroxylated intermediates and in the fact that the secretion of C(19) steroids takes place, in some species, exclusively in the gonads. Ovine CYP17 expressed in HEK 293 cells converts progesterone to 17-hydroxyprogesterone and pregnenolone to dehydroepiandrosterone via 17-hydroxypregnenolone. In ovine adrenal microsomes, minimal if any lyase activity was observed toward either progesterone or pregnenolone. Others have demonstrated the involvement of cytochrome b(5) in the augmentation of CYP17 lyase activity. Although the presence of cytochrome b(5) in ovine adrenocortical microsomes was established, ovine adrenal microsomes did not convert pregnenolone or 17-hydroxypregnenolone to dehydroepiandrosterone. Furthermore the addition of purified ovine cytochrome b(5) to ovine adrenal microsomes did not promote lyase activity. We conclude that, in the ovine adrenal cortex, factors other than cytochrome b(5) influence the lyase activity of ovine CYP17.
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Affiliation(s)
- Pieter Swart
- Department of Biochemistry, University of Stellenbosch, South Africa
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13
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Lombard N, Swart AC, van der Merwe MJ, Swart P. Sheep adrenal cytochrome b5: active as a monomer or a tetramer in vivo? Endocr Res 2002; 28:485-92. [PMID: 12530653 DOI: 10.1081/erc-120016827] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Cytochrome b5 (cyt b5) is an ubiquitous hemoprotein also associated with microsomal cytochromes P450. It has been reported that cyt b5 influences cytochrome P450-dependent catalyses through electron transport as well as direct protein-protein interactions. To investigate the influence of cyt b5 on ovine adrenal steroidogenesis, we isolated and characterized cyt b5 from ovine liver. The molecular mass of the purified protein was 15,260 as determined by electrospray mass spectrometry. SDS-Polyacrylamide gel electrophoresis, even after stringent detergent and mercaptoethanol pretreatment, indicated multimeric forms of the protein, the most prominent being the tetramer (+/-60 kDa) with minor bands corresponding to the monomer (+/-16 kDa) and dimer (+/-30 kDa). Trypsin treatment of cyt b5 resulted in a truncated enzyme with a molecular mass of +/-10 kDa. The aggregation of cytochrome b5 was abolished by the tryptic removal of the membrane binding region. In Western blot analyses antibodies against the truncated protein recognised only this low molecular mass form and not the full length cyt b5, or any of the higher molecular complexes, showing the involvement of the membrane binding domain of the protein, not only in aggregation, but also in the quaternary structure which determines epitope presentation for antibody production. Immunoblot analyses of sheep adrenal microsomes with the anti-truncated cyt b5 antibody were also negative. Immunoblot analyses and immunocytochemistry of adrenal tissue with antibodies against the full length cyt b5 indicated that the tetrameric form of the protein was in all probability the dominant specie in vivo.
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Affiliation(s)
- Nicolaas Lombard
- Department of Biochemistry, University of Stellenbosch, Matieland 7602, South Africa
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DE Kock M, Theron KI, Swart P, Weiler EW, Bellstedt DU. Cytokinins in the xylem sap of the dioecious fynbos shrub, Leucadendron rubrum Burm. f.: seasonal fluctuations and their possible interaction with morphological characteristics as expressed in the two sexes. THE NEW PHYTOLOGIST 1994; 127:749-759. [PMID: 33874384 DOI: 10.1111/j.1469-8137.1994.tb02979.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Brandies of male and female plants of the dioecious Leucadendron rubrum Burm. f. were collected on the site of the Weikamp weather-station in the Jonkershoek State Forest, Stellenbosch, from July 1990 to September 1991. Xylem sap was extracted from the branches by vacuum extraction. HPLC was employed to purify the xylem sap and to separate the cytokinins prior to quantitation by ELISA. The cytokinin levels in the purified plant samples were determined using rabbit antiserum-based ELISAs for the determination of the levels of the cytokinins DHZR and IPA, and a trans-ZR specific monoclonal antibody-based ELISA for the determination of the levels of the cytokinin ZR. It was observed that the levels of the cytokinins DHZR and ZR did not differ significantly between male and female plants but did correlate with the seasonal growth patterns. The levels of the cytokinin IPA, in male and female plants of L. rubrum, not only correlated specifically with the different seasonal growth patterns observed but differed significantly between male and female plants. Peaks in the levels of all three cytokinins. i.e. ZR, DHZR and IPA, occurred during the study period. These peaks corresponded with the phenological development of L. rubrum, specifically with vegetative bud break and inflorescence differentiation and appeared to be synchronized with the growth and development. An attempt was also made to correlate cytokinin levels with the extreme differences in morphological characters exhibited by male and female plants, and possibly to explain to what extent these phytohormones influence sex expression in L. rubrum.
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Affiliation(s)
- Marianna DE Kock
- Department of Biochemistry, University of Stellenbosch, Stellenbosch 7600, South Africa
| | - Karen I Theron
- Department of Horticultural Science, University of Stellenbosch, Stellenbosch 7600, South Africa
| | - Pieter Swart
- Department of Biochemistry, University of Stellenbosch, Stellenbosch 7600, South Africa
| | - Elmar W Weiler
- Lehrstuhl für Pflanzenphysiologie, Ruhr Universität, D-44780 Bochum, Germany
| | - Dirk U Bellstedt
- Department of Biochemistry, University of Stellenbosch, Stellenbosch 7600, South Africa
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15
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Ralchev KH, Petkov PM, Dunkov BH. Purification and characterization of diaphorases from someDrosophila species. Biochem Genet 1992. [DOI: 10.1007/pl00020474] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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16
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Ralchev KH, Petkov PM, Dunkov BH. Purification and characterization of diaphorases from some Drosophila species. Biochem Genet 1992; 30:305-15. [PMID: 1616484 DOI: 10.1007/bf02396219] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Diaphorase-1 and diaphorase-2 were isolated from two Drosophila species, D. virilis and D. melanogaster, and purified by gel filtration, affinity chromatography, immunoaffinity chromatography, and ion-exchange chromatography. The molecular weights of both enzymes were the same in each species. The molecular weight of diaphorase-1 was the same under both denaturating and nondenaturating conditions, close to 60,000, indicating a monomeric structure. Sodium dodecyl sulfate (SDS) electrophoresis of the purified diaphorase-2 revealed the presence of a single protein band of 55,000 Da, while the molecular weight of the native enzyme was found to be 67,000. The two diaphorases were further characterized by their pH optima, isoelectric points, and kinetic parameters, and antibodies were raised in rabbits against the purified enzymes from D. virilis. The antibodies showed no cross-reactions but recognized the corresponding diaphorases in D. melanogaster and D. novamexicana as well as D. virilis. The data obtained confirmed the hypothesis of an independent genetic control of diaphorase-1 and diaphorase-2 in Drosophila.
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Affiliation(s)
- K H Ralchev
- Chair of Genetics, Faculty of Biology, Sofia University, Bulgaria
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17
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Dinjens WN, Van der Linden EP, Signet CM, Wijnen JT, Meera Khan P, Ten Kate J, Bosman FT. Solid-phase adsorption of antigens for efficient production of antibodies reactive with native and fixed tissue antigens. J Immunol Methods 1990; 126:175-82. [PMID: 2406345 DOI: 10.1016/0022-1759(90)90148-o] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
A study has been made of the efficacy of different immunization protocols using low antigen levels for the generation of monoclonal antibodies capable of detecting antigens (ADCP) in processed tissues. Protocols using unprocessed native antigen immobilized on nitrocellulose were more efficient than soluble antigen in generating serum antibodies reactive with both native antigen and processed tissues. The derived monoclonal antibodies reacted with native but not processed antigen. The use of antigen immobilized on polyvinylidene (PVDF) and subsequently processed as for histochemistry was successful in generating monoclonal antibodies reactive with processed antigen.
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Affiliation(s)
- W N Dinjens
- Department of Pathology, University of Limburg, Maastricht, The Netherlands
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18
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Cilliers JM, Stindt HW, Bellstedt DU. The production of highly specific anti-testosterone antisera using acid-treated bacteria as immunogenic carrier. Immunol Invest 1989; 18:1035-48. [PMID: 2613285 DOI: 10.3109/08820138909030605] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
A novel and effective procedure for the production of highly specific anti-testosterone antibodies is described. It involved pretreatment of experimental animals with tolerogens followed by immunization with conjugates of testosterone covalently linked to acid-treated Salmonella minnesota R595 bacteria as immunogenic carriers. Antibodies elicited by this procedure showed minimal cross-reactivity towards 5 alpha-dihydrotestosterone and some of them were successfully used in radioimmunoassays for the determination of serum testosterone levels, even without the need for prior extraction.
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Affiliation(s)
- J M Cilliers
- Department of Biochemistry, University of Stellenbosch, Republic of South Africa
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Strachan AF, Shephard EG, Bellstedt DU, Coetzee GA, van der Westhuyzen DR, de Beer FC. Human serum amyloid A protein. Behaviour in aqueous and urea-containing solutions and antibody production. Biochem J 1989; 263:365-70. [PMID: 2597108 PMCID: PMC1133438 DOI: 10.1042/bj2630365] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Human serum amyloid A protein (apo-SAA) can be prepared by gel filtration of delipidated acute-phase high-density lipoprotein in the presence of urea. The resultant apo-SAA is soluble (greater than 90% solubility) in a wide range of buffer solutions, with all of the six major isoforms of apo-SAA being equally soluble. In urea-containing solutions the isoforms behave qualitatively differently in various urea concentrations, probably reflecting subtle primary-structure variations. The higher-pI isoforms are only completely unfolded at greater than 7 M-urea. By immunizing with apo-SAA adsorbed to acid-treated bacteria (Salmonella minnesota R595), high-titre antibodies can easily be elicited in rabbits.
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Affiliation(s)
- A F Strachan
- Department of Internal Medicine, University of Stellenbosch Medical School, Tygerberg, South Africa
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Rowland GF, Engelbrecht DJ, Pool EJ, Schmollgruber EC, Thompson GJ, van der Merwe KJ. The use of peroxidase anti-peroxidase (PAP) complexes in the detection of plant viruses by ELISA. J Virol Methods 1989; 25:259-69. [PMID: 2685004 DOI: 10.1016/0166-0934(89)90053-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
An ELISA test system for detection of plant viruses in field samples is described, based on the unlabelled antibody method using a peroxidase-antiperoxidase (PAP) complex. Novel features of the system include the use of acid-treated naked bacteria as combined carrier-adjuvants for the production of rabbit antiviral antibodies, and the use of acid-treated chicken antibodies (IgY) for antigen trapping in the ELISA. Systems for detection of potato virus Y (PVY), potato leafroll virus (PLRV), grapevine fanleaf virus (GFV) and grapevine virus A (GVA) were developed and compared with conventional direct double antibody sandwich (DAS) systems in tests with both purified virus and field samples. The PAP systems offer improved sensitivity, no background problems in the outer rows of the microtitre plates and are much easier to visualize with the naked eye if no plate reader is available.
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Affiliation(s)
- G F Rowland
- Bioclones (Pty) Ltd, c/o Department of Biochemistry, University of Stellenbosch, Republic of South Africa
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21
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Bellstedt DU, Van der Merwe KJ, Galanos C. Immune carrier properties of acid-treated Salmonella minnesota R595 bacteria. The immune response to TNP-bacterial conjugates in rabbits and mice. J Immunol Methods 1988; 108:245-54. [PMID: 3280687 DOI: 10.1016/0022-1759(88)90426-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Salmonella minnesota R595 bacteria from which the core region of the lipopolysaccharide on the cell wall had previously been removed by mild acid treatment were trinitrophenylated. Differing amounts of these trinitrophenyl naked bacterial conjugates (TNP-NB), covering a range of epitope densities, were used for immunising mice and rabbits via the intraperitoneal or intravenous routes without adjuvants. It was found that such acid-treated, naked bacteria were effective carriers for the covalently linked hapten, TNP, with an optimum epitope density of 15 micrograms TNP/mg NB. Significant immune responses were obtained with dose levels as low as 50 ng TNP. The possible applications of acid-treated, naked bacteria as universal carriers having inherent adjuvant activity are discussed.
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Affiliation(s)
- D U Bellstedt
- Max-Planck-Institut für Immunbiologie, Freiburg, F.R.G
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