Genetic variation and relationship in Staphylococcus aureus isolates from human and food samples using random amplified polymorphic DNAs

A genetic characterization of 18 different isolates of Staphylococcus aureus using random amplified polymorphic DNAs (RAPDs) was carried out. Out of one hundred primers tested, ten showed polymorphism. The amplification reactions with the 10 primers generated 88 bands, 51 of which is polymorphic with band size ranging between 200 and 3,000 bp. Variation and relatedness between different isolates were determined by converting RAPD data into a Jaccard similarity matrix and analysed by UPGMA (unweighted pair-group method, arithmetic average) to produce completely twelve different groups at 100% Jaccard similarity and at 50% coefficient of similarity. The isolates were classified into two major groups, the first comprises of mildly and weakly virulence, while the other group are the highly virulence Staphylococci. The results demonstrated that the RAPD technique may be of great use in the classification of Staphylococcus aureus.African Journal of Biotechnology Vol. 4 (7), pp. 611-614, 200

Genetic Analysis and Molecular Identification of Virulence in Xanthomonas oryzaepv.oryzaeIsolates

Bacterial leaf blight (BLB) of rice is a very destructive disease worldwide and is caused byXanthomonas oryzaepv.oryzae(Xoo).The aimofthepresentstudywastoexamineiftheXoovirulence pathotypes obtained using phenotypic pathotyping could be confirmed using molecular approach. After screening of 60 Operon primers with genomic DNA of twoXooisolates (virulent pathotype,Vr, and mildly virulent pathotype,MVr), 12 Operon primers that gave reproducible and useful genetic information were selected and used to analyze 50Xooisolates from 7 West African countries. Genetic analysis revealed two majorXoovirulence genotypes (Mta andMtb)withMtahaving two subgroups (Mta1andMta2).Mta1(Vr1) subgroup genotype has occurrence in six countries and Mta2(Vr2) in three countries whileMtbgenotype characterized mildly virulence (MVr)Xooisolates present in five countries. The study revealed possible linkage and correlation between phenotypic pathotyping and molecular typing ofXoovirulence.Xoo virulence genotypes were known to exist within country and there was evidence ofXoopathogen migration between countries. Durable resistance rice cultivars would need to overcome bothMtaandMtb Xoovirulence genotypes in order to survive after their deployment into different rice ecologies in West Africa

Genetic Analysis of Effect of Heat Stress on Genomic DNA from Cowpea ( Vigna unguiculata (L) Walp.)

Aims: Genetic analysis was used to study the effect of heat st ress on young seedlings of cowpea ( Vigna unguiculata (L) Walp.). Study Design: Four different colors of cowpea seeds (white, dirty w hite, deep brown and light brown) were obtained from GeneBank of International Institute of Tropical Agriculture (IITA) Ibadan, Nigeria. Seeds from each of the cowpea four colors we re first pre-germinated and young seedlings subjected to DNA extraction. Extracted DNA subjected to different temperature treatments at 75°C and 100°C for one hour and control not heated. Place and Duration of Study: Department of Chemical Sciences Afe Babalola University Ado Ekiti, Nigeria between January 2015 and June 2015. Methodology: UV wavelength absorption spectrum analysis (A 200 – A 960 ) was carried out on control DNA and DNA heated at 75°C and 100°C respectively. Cl uster analysis of optical density (OD) data was carried out to establish the relationship between co ntrol DNA and heat treated DNA (75°C and 100°C). Results: DNA concentrations of Vigna unguiculata (L) Walp. were between 0.40 to 1.15 mg/ml, 0.33 to 0.84 mg/ml, and 0.26 to 0.89 mg/ml for control a nd heat treatments of 75°C and 100°C respectively. DNA UV absorption spectra of control and heat treatments of 75°C and 100°C were generally different due to differential UV wavelengt h absorption. Cluster analysis revealed three different clusters (cluster 1, cluster 2 and cluster 3) among control DNA and heat treated DNA. Cluster 1 comprised of V1-control, V1-75°C and V1-10 0°C, with V1-75°C and V1-100°C having similar characters. Cluster 2 was made up of V4-control, V4-75°C and V4-100°C, with V4-75°C and V4-100°C having the same characters. Cluster 3 was largel y characterized by dissimilar DNA extracts of V3-75°C, V2-control, V3-100°C, V2-100°C, V 3-control and V2-75°C. Conclusion: Genetic diversity among individual Vigna unguiculata (L) Walp. accession DNA as obtained in this study could possibly be as a result of variations in heat tolerance among dissimilar cowpea genomic composition

Effects of biofertilizer containing N-fixer, P and K solubilizers and AM fungi on maize growth: A greenhouse trial.

An in vitro study was undertaken to evaluate the compatibility of indigenous plant growth promoting rhizobacteria (PGPR) with commonly used inorganic and organic sources of fertilizers in tea plantations. The nitrogenous, phosphatic and potash fertilizers used for this study were urea, rock phosphate and muriate of potash, respectively. The organic sources of fertilizers neem cake, composted coir pith and vermicompost were also used. PGPRs such as nitrogen fixer; Azospirillum lipoferum, Phosphate Solubilizing Bacteria (PSB); Pseudomonas putida, Potassium Solubilizing Bacteria (KSB); Burkholderia cepacia and Pseudomonas putida were used for compatibility study. Results were indicated that PGPRs preferred the coir pith and they proved their higher colony establishment in the formulation except Azospirillum spp. that preferred vermicompost for their establishment. The optimum dose of neem cake powder

Serum biochemical parameters and cytokine profiles associated with natural African trypanosome infections in cattle.

BACKGROUND: Animal African trypanosomiasis (AAT) greatly affects livestock production in sub-Saharan Africa. In Ghana prevalence of AAT is estimated to range between 5 and 50%. Studies have reported serum biochemical aberrations and variability in cytokine profiles in animals during infection. However, information regarding the biochemical parameters and cytokine profiles associated with natural infections are limited. This study was therefore aimed at investigating changes in the levels of serum biochemical parameters and inflammatory cytokines during a natural infection. METHODS: Nested internal transcribed spacer (ITS)-based PCR and sequencing were used to characterise trypanosome infection in cattle at two areas in Ghana (Adidome and Accra) of different endemicities. The cattle were sampled at four to five-week intervals over a period of six months. Levels of serum biochemical parameters, including creatinine, cholesterol, alkaline phosphatase (ALP), alanine aminotransferase (ALT), total bilirubin and total protein and cytokines (interleukin 10, interleukin 4, interleukin 12, interferon gamma and tumor necrosis factor alpha) were measured in serum samples and then compared between infected cattle and uninfected controls. RESULTS: The predominant trypanosome species detected in Accra (non-endemic) and Adidome (endemic) were Trypanosoma theileri and Trypanosoma vivax, respectively. Serum biochemical parameters were similar between infected and uninfected cattle in Accra. Infected cattle at Adidome however, had significantly higher levels of ALP, creatinine, total protein and total bilirubin (P < 0.05) and significantly lower levels of cholesterol (P < 0.05) at specific time points. At basal levels and during infection, significantly higher pro-inflammatory to anti-inflammatory (Th1/Th2) cytokine ratios were observed in cattle at Adidome compared to Accra (P < 0.05), indicating a shift towards Th1 immune response in Adidome. Levels of IL-10 were, however, significantly elevated in infected cattle in Accra (P < 0.05), suggesting high anti-inflammatory cytokine response in Accra. CONCLUSION: These results suggests that cattle in an endemic area repeatedly infected with trypanosomes of different species or different antigenic types demonstrate high pro-inflammatory (Th1) immune response and biochemical alterations whereas cattle in a non-endemic area with predominantly chronic T. theileri infections demonstrate high anti-inflammatory response and no biochemical alterations

Identification and potential use of RAPD markers linked to yam mosaic virus resistance in white yam (Dioscorea rotundata)

Resistance to Yam mosaic virus (YMV) in tetraploid white yam (Dioscorea rotundata) is inherited differentially as a dominant and recessive character. Elite D. rotundata breeding lines with durable resistance to YMV can be developed by pyramiding major dominant and recessive genes using marker assisted selection (MAS). The tetraploid breeding line, TDr 89/01444, is a source of dominant genetic resistance to yam mosaic disease. Bulked segregant analysis was used to search for random amplified polymorphic DNA (RAPD) markers linked to YMV resistance in F1 progeny derived from a cross between TDr 89/01444 and the susceptible female parent, TDr 87/00571. The F1 progeny segregated 1:1 (resistant: susceptible) when inoculated with a Nigerian isolate of YMV, confirming that resistance to YMV in TDr 89/01444 was dominantly inherited. A single locus that contributes to YMV resistance in TDr 89/01444 was identified and tentatively named Ymv-1. Two RAPD markers closely linked in coupling phase with Ymv-1 were identified, both of which were mapped on the same linkage group: OPW18850 (3.0 centiMorgans [cM]) and OPX15850 (2.0 cM). Both markers successfully identified Ymv-1 in resistant genotypes among 12 D. rotundata varieties and in resistant F1 individuals from the cross TDr 93-1 ´ TDr 87/ 00211, indicating their potential for use in marker-assisted selection. OPW18850 and OPX15850 are the first DNA markers for YMV resistance and represent a starting point in the use of molecular markers to assist breeding for resistance to YMV

Proteomic Quantitative UV Absorption Spectrum Analysis of Effect of Heat Stress on Protein Extract from Cowpea Seed (Vigna unguiculata (L) Walp)

Aim: Proteomic quantitative UV absorption spectrum analysis was used to study the effect of heat stress on protein extract from cowpea seeds (Vigna unguiculata (L) Walp). Study Design: Protein extracts were obtained from 9 cowpea accessions obtained from GeneBank of International Institute of Tropical Agriculture in January 2014. Each protein extract was divided into four batches out of which three batches were subjected to different temperature treatments and incubation at 37°C, 60°C and 100°C for 1 hour and the remaining one batch served as control. Protein content in each control protein extract and 37°C, 60°C and 100°C treated protein extracts from each of the 9 cowpea samples were determined at 280 nm using bovine serum albumin standard curve. Place and Duration of Study: Biochemistry Unit, Department of Chemical Sciences, Afe Babalola University Ado Ekiti, Nigeria between January 2014 and June 2014. Methodology: A200-A960 UV wavelengths absorption spectrum analysis was carried out on control protein extract and 37°C, 60°C and 100°C treated protein extracts respectively from each of the 9 cowpea samples. In order to establish the relationship between protein extracts (control) and protein extracts heat treated (37°C, 60°C, and 100°C), cluster analysis of optical density (OD) data was carried out using numerical taxonomy and multivariate analysis system. Results: The protein content (control) in Vigna unguiculata (L) Walp was between 8.4 and 10.8 mg/ml (10.5-13.5%) in seed, while protein content (heat treated) in Vigna unguiculata (L) Walp was between 8.9 and 9.5 mg/ml (11.2-11.9%), 8.7-9.5 mg/ml (10.9-11.9%), 9.0 and 11.8 mg/ml (11.3- 14.7 %) in heat treatments of 37°C, 60°C, and 100°C respectively. The protein UV absorption spectra of control protein extract and 37°C, 60°C and 100°C treated protein extracts from each cowpea accession were generally different due to differential UV wavelength protein absorption. Cluster analysis of absorbance spectra optical density values revealed five clusters (cluster 1, cluster 2, cluster 3, cluster 4, and cluster 5) among control protein extracts and protein extracts heated at 37°C, 60°C, and 100°C. Cluster1 was made up of protein extracts heated at 37°C and 60°C, while cluster2 and cluster3 constituted closely related protein extracts heated at 37°C and 100°C respectively. Cluster4 was typical of control protein extracts, while cluster5 was made up of distinct protein extracts heated at 100°C. Conclusion: Heating protein extracts at 37°C, 60°C, and 100ºC has altered proteomic diversity in different cowpea accessions and this could make protein extraction more difficult with implications on protein properties