Flagellar motility plays important role in Biofilm formation of Bacillus cereus and Yersinia enterocolitica

Bacteria live either independently as planktonic cells or in organized surface associated colonies called as biofilms. Biofilms play an important role in increased pathogenesis of bacteria and it is assumed that motility is one of the contributing factors towards biofilm initiation. This study was planned to identify the role of flagella in biofilm formation by constructing flagellated [wild type] and physically disrupted variants [non-motile]. Total 10 clinical bacterial strains were isolated and characterized. Morphological and biochemical study identified these strains as Enterobacter spp., Pseudomonas spp., Yersinia spp., Escherichia spp., Salmonella spp., Proteus spp., Staphylococcus spp., Streptococcus spp., Lactobacillus spp. and Bacillus spp. Among all strains, two strains including Yersinia spp and Bacillus spp. showed higher antibiotic resistance, hence studied at molecular and physiological level. Biofilm formation capacity of strains was analyzed using three methods including Congo red assay, Test tube assay and Liquid-interface coverslip assay. Afterwards, flagellar disintegration was induced by blending and centrifugation for 5, 10 and 15 minutes. 16S rRNA sequencing showed two strains as Bacillus cereus and Yersinia enterocolitica. Both strains produced significant biofilm by all three above mentioned methods. A motility test of these blended variants showed partial/diminished motility with increased blending time. The significant loss in biofilm formation after 15 minutes blending confirmed the important flagellar contribution to the initiation of biofilm formation. This biofilm defect observed in flagella paralysed/minus variants presumably may be due to defects in attachments to surface at early stages. This study indicated that flagellar motility is crucial initially for surface attachment and subsequently for biofilm formation

Effect of medicinal plants, Heavy metals and antibiotics against P pathogenic bacteria isolated from raw, Boiled and pasteurized milk

Present study has been undertaken to isolate and identify the bacterial flora in raw, boiled and pasteurized milk. Agar disc diffusion method was used to determine their sensitivity using medicinal plants, antibiotics and heavy metals. Methylene blue reduction test was used to test the quality of milk samples. Total 10 pathogenic strains were isolated, five strains were isolated from raw milk, three from boiled milk and 2 two from pasteurized milk. To determine optimum conditions for growth, these pathogenic microorganisms were incubated at various temperatures and pH. Gram's staining and biochemical tests revealed that these pathogenic bacteria include Lactobacillus sp., E. coll, Salmonella sp., Pseudomonas sp., Streptococcus sp. and Staphylococcus. Ribotyping revealed S2 as Pseudomonas fluorescens, S5 as Lactococcus lactis and S9 as Lactobacillus acidophilus. Prevalence of pathogenic organisms provided the evidence that contamination of milk arises during milking, transportation and storage of milk. Raw milk is more contaminated than other two types of milk because it contains highest percentage of pathogenic organisms and pasteurized milk was found to be of best quality among three types. So it is recommended to drink milk after proper boiling or pasteurization. Proper pasteurization and hygienic packing of milk is essential to minimize contamination in milk which can save human beings from many milk borne diseases. Our study suggests that antimicrobial use in animal husbandry should be minimized to reduce the hazard of antibiotic resistance. Plant extracts are better alternative against pathogenic bacteria in milk

Association of rs1800668 polymorphism in glutathione peroxidase- 1 gene and risk of rheumatoid arthritis in Pakistani population

Objective: To investigate the role of glutathione peroxidase 1 [GPX1] C/T polymorphism [rs1800668] in modulating the chances of Rheumatoid arthritis [RA] in Pakistani population

Methods:A total of 400 individuals including 200 controls and 200 patients of RA, were genotyped. Detection of rs1800668 polymorphism was carried out using PCR based amplification strategy [allele specific]

Results:The results for Hardy Weinberg Equilibrium [HWE] indicated that the allele frequencies for GPX1 polymorphism were not deviant from HWE in whole population under observation. The statistical analysis indicated that significant association existed between rs1800668 polymorphism and RA [p<0.01]. CT genotype increased the risk of RA development by 1.8582 times [OR: 1.8582; 95% CI 1.2154 to 2.8409]. CC genotype was found to have protective effect against the disease development [OR: 0.5133; 95% CI 0.3403 to 0.7742] while TT genotype was found to have association with RA development but the risk level was marginal [OR: 1.5319; 95% CI 0.6124 to 3.8322]

Conclusion:The present finding suggests the importance of GPX1 C/T polymorphism [rs1800668] in development of RA in Pakistani population. The protective role of CC genotype against the development of RA in local population was also observed