African Journals On-line
African Journal of Biotechnology

Volume 2 Number 7 July 2003
ABSTRACTS

Production of monoclonal and polyclonal antibodies against a Nigerian isolate of banana streak virus

Agindotan B.O. ^1,2,*, Thottappilly G.^2,l, Uwaifo A¹ and Winter S³

¹Biochemistry Department, University of Ibadan, Ibadan, Nigeria

²International Institute of Tropical Agriculture, Ibadan, Nigeria.

³DSM-Deutsche Sammlung von Mikroorganismem und Zellkulturen Abt. Pflanzenviren, Braunschweig, Federal Republic of Germany

*Corresponding Author; Present address: Plant, Soil and Entomological Sciences Dept., University of Idaho, Moscow, ID 83844, USA, e-mail: [email protected],  fax: +1-208:8857760, tel: +1-208-885-5827.

¹Present address: Mahyco Research Foundation, Kamalapuri colony, Hyderabad- 500073, India.

Abstract

Banana streak virus is serologically and genomically heterogenous worldwide and there has been the need to produce antibodies that can detect all known serotypes of this virus. Antibody production requires purified virus, since BSV titre is low in Musa tissues, there was the need for an efficient method of purifying the virus. We are reporting the first production of two monoclonal antibodies, BSV 3F9/1 and BSV 3D4/2, against an isolate of BSV. Culture fluids of BSV 3F9/1 and BSV 3D4/2 had antibody titres of 1:204,000 and 1:6400, by ELISA, respectively. The two monoclonal antibodies detected all isolates of BSV that were detected by the homologous mouse polyclonal antibodies. Caesium gradient centrifugation reduced yield of BSV during purification. We described a method of purification, which excluded the caesium gradient step and yet increased BSV yield by about 15-fold. The virus preparation obtained by this new method was used to produce BSV-specific mouse and rabbit polyclonal antibodies. These BSV monoclonal antibodies together with the polyclonal antibodies were used for the detection of BSV.

Key words: Banana streak virus, monoclonal antibodies, polyclonal antibodies, Musa, TAS-ELISA, polysynthetic antibodies, antigen-coated dot ELISA.

Influence of cultural conditions on the production of bacteriocin by Lactobacillus brevis OG1

S.T. Ogunbanwo*, A.I. Sanni, and A. A. Onilude

Department of Botany and Microbiology, University of Ibadan, Nigeria

*Corresponding author: Fax: 234-02-8103043; 8103118; e-mail: [email protected] 

Abstract

Bacteriocin produced by Lactobacillus brevis OG1 has large spectrum of inhibition against pathogenic, food spoilage microorganisms and various Lactic acid bacteria employed as test strains. The bacteriocin inhibited E coli NCTC 10418 and Enterococcus faecalis, but did not inhibit Candida albicans ATCC 10231 and Klebsiella sp. UCH 15. The antibacterial activity appeared to be pronounced between early logarithmic and early stationary phase. Supplementation and/or replacement of nutrients demonstrated that larger quantities of bacteriocin could be produced by addition of yeast extracts (3.0%), NaCl (1.0-2.0%), glucose (1.0 %) and Tween 80 (0.5%), while addition of tri-ammonium citrate, sodium acetate, magnesium sulphate, manganese sulphate and potassium phosphate had no effect on production. Maximal activity in composed medium was achieved at initial pH of 5.5, and incubation period of 48h at 30-37ºC.

Key words: Bacteriocin, growth media, Lactobacillus brevis OG1, indicator organisms, antagonistic activity.

Analysis of AVR4 promoter by sequential response-element deletion

Olukosi, YA¹ and Iwalokun, BA²*

¹Genetics Division, Nigerian Institute of Medical Research (NIMR), 6, Edmond Crescent, Yaba – Lagos, PMB 2013, Lagos - Nigeria.

²Biochemistry Dept, Lagos State University, PMB 1087, Apapa – Lagos, Nigeria.

*Corresponding author: E-mail: [email protected] 

Abstract

Several reports have associated the variability in physico-chemical properties of avidin protein to dynamism inherent in the consensus regulatory networks within the promoter region of avidin genes. An Avr4 promoter region ligated to chloramphenicol acetyltransferase plasmid vector (pBLCAT2) to produce recombinant plasmid Avr4pBLCAT2 was sequentially deleted to produce five distinct mutants: Avr4pBLCAT2_907-176, Avr4pBLCAT2_809-176, Avr4pBLCAT2_789-176, Avr4pBLCAT2_429-176 and Avr4pBLCAT2 _302-176. The transformants elicited different chloramphenicol acetyl transferase (CAT) activities.

Key words: Avidin, AVR4 promoter, chloramphenicol acetyl transferase.

Efficacy of IgG, Fab, and F(ab')₂ fragments of horse antivenom in the treatment of local symptoms after Cerastes cerastes (Egyptian snake) bite

Salwa S. Abdel Latif¹*, Soheir Wanas¹, George Abdel Malak¹ and Madiha H. Helmy²

¹Egyptian Organization for Biological Products and Vaccines (VACSERA), 51 Wezaret Elzeraa St., Agouza, Giza

²Biochemistry Research Institute, Alexandria university, 165 ElHoria Road, El-Hadra region, Egypt.

*Corresponding author: E-mail: [email protected],  Fax: (+202) 3369872-7483187-7609177

Abstract

The ability of horse antivenoms, consisting of immunoglobulin G (IgG) and its fragments F(ab')₂ and Fab were comparatively studied in mice to neutralize several effects of Cerastes cerastes venom. The three antivenoms were produced from the same batch of hyperimmune horse plasma. Neutralization was only partial when antivenins were administered intravenously at various time intervals after envenomation. No significant differences were observed among IgG, Fab, and F(ab')₂ antivenoms concerning neutralization of hemorrhagic effects. Fab fragments were slightly more effective in neutralizing edema while IgG and F(ab')₂ antivenoms were better in neutralizing myonecrosis in experiments involving independent injection of venom and antivenom.Thus these results disagree with the theory that "Fab " fragments are more effective than whole IgG and F(ab')₂ in the neutralization of local symptoms accompanying C. Cerastes venom.

Key words: Cerastes cerastes, Egyptian snake, IgG, F(ab')₂, Fab.

Genetics similarity among four breeds of sheep in Egypt detected by random amplified polymorphic DNA markers

Bahy Ahmed Ali

Nucleic Acid Research Dept., Genetic Engineering and Biotechnology Research Institute (GEBRI), Mubarak City for Scientific Research & Technology Applications, Alexandria, Egypt. E-mail: [email protected]  or [email protected],  Fax: 203 4593423

Abstract

A genetic analysis using RAPD markers was performed for studying variation in four breeds of sheep (Baladi, Barki, Rahmani and Saffolk). Nineteen random primers were used to amplify DNA fragments in these breeds. RAPD patterns with a level of polymorphism were detected between breeds. Results showed closer proximity of Barki to Rahmani and Baladi (95.7 and 91.3%), respectively.

Keywords: Sheep, breeds, RAPD, genetic similarity.

Nodulation and nitrogen fixation of field grown common bean (Phaseolus vulgaris) as influenced by fungicide seed treatment

Ndeye Fatou Diaw GUENE, Adama DIOUF and Mamadou GUEYE*

MIRCEN/ Laboratoire commun de microbiologie IRD-ISRA-UCAD, BP 1386, DAKAR, Senegal

*Corresponding author; phone: +221-8493321, fax: +221-8321675; e-mail: [email protected] 

Abstract

A field experiment was conducted at Bel Air station, in Dakar using ¹⁵N isotope dilution technique and the non nodulating soybean (Glycine max) variety m129 as reference plant to test the compatibility of Dichlorofenthion-thiram (DCT) fungicide to the inoculation of common bean (Phaseolus vulgaris) Paulista variety with both Rhizobium etli ISRA 353 and R. tropici strain ISRA 554. Nodulation was not induced with R. etli ISRA 353 and nitrogen fixation did not occur. With R. tropici ISRA 554, a decrease in nodulation was observed, but nitrogen fixation was not significantly different compared to that of the non DCT-treated common bean.

Key words: Common bean, fungicides, isotope dilution, ¹⁵N, nitrogen fixation, nodulation, Phaseolus vulgaris, Rhizobium.

Inheritance of resistance to head bug (Eurystylus oldi) in grain sorghum (Sorghum bicolor)

S. E. Aladele¹* and I. E. Ezeaku²

¹ National Centre for Genetic Resources and Biotechnology, P.M.B. 5382, Ibadan, Nigeria

²International Crops Research Institute for the Semi-Arid Tropics, P.M.B. 3491, Kano, Nigeria

*Corresponding author: E-mail: [email protected] 

Abstract

The inheritance of resistance to head bug (Eurystylus oldi) was studied in ten populations of sorghum derived from crossing three susceptible sorghum elite varieties (ICSV 111, ICSV 112 and ICSV 400), and two resistant sorghum varieties (Malisor 84-7 and KSV 4). Parental lines, F₁ and F₂ populations were sown on a Randomized Complete Block Design in two replications. Artificial infestation of head bugs on sorghum was employed in carrying out the experiment. Samples of 5 panicles each from every artificially infested plot were observed. Resistance to head bug in sorghum seems to be controlled by a single pair of recessive genes in Malisor 84-7 x ICSV 400 and Malisor 84-7 x ICSV 111. The cross, KSV 4 x ICSV 112 appeared to be controlled by double recessive pair of genes. Head bug population affects quality of grains rather than the yield produced. There is a negative correlation (-0.095) between head bug population and the germination percentage of the grain. Positive relationship exists between glume size and head bug population, which suggests that longer glumes harbour more head bug.

Key words: Head bug (Eurystylus oldi), Infestation, Anthesis, Resistance, Susceptible, Inheritance.

Comparison of multi-locus enzyme and protein gel electrophoresis in the discrimination of five Fusarium species isolated from Egyptian cottons

Ibrahim N. Aly¹, Mohmed A. Abdel-Sattar¹, Kamel A. Abd-Elsalam^2,3* Mohmed S. Khalil² and Joseph A. Verreet³

¹ Suez Canal University, Faculty of Agriculture, Ismailia, Egypt.

² Agricultural Research Center, Plant Pathology Research Institute, Giza, Egypt.

³ Christian Albrechts Universität zu Kiel, Institut für Phytopathologie, Kiel, Germany.

*Corresponding author; phone: (49 431) 880 2993; fax: (49 431) 880 1583; e-mail: [email protected] 

Abstract

Electrophoretic studies of multilocus-enzymes (MLEE) and whole-cell protein (SDS-PAGE) were carried out in order to evaluate the parity between different methods for the characterization of five Fusarium species recovered from cotton-growing areas in Egypt by numerical taxonomy methods. The obtained data revealed that SDS-PAGE and esterase isozymes are more efficient in grouping isolates in their respective species while peroxidase and malate dehydrogenase isozyme has much limited resolution in organizing all isolates in their respective species-specific clusters. A low correlations was detected between geographical origin of isolates and genetic diversity. Results indicate that the estimated inter-specific variation may be more pronounced with protein markers than with isoyzmes when the two approaches are applied to the same populations. The level of genetic variability detected within and between Fusarium spp. accessions with protein and esterase isoyzmes analysis suggests that it is a reliable, efficient, and effective marker technology for determining genetic relationships in Fusarium genus.

Key words: Cotton, Fusarium, Isozymes, polyacrylamide gel electrophoresis.