Isolation and Characterization of L-Glutaminase producing Bacteria

Abstract

AbstractBeing a significant protein L-glutaminases discovers potential applications in various divisions running from nourishment industry to restorative and cure. It is generally disseminated in microbes, actinomycetes, yeast and organisms. Glutaminase is the principal enzyme that changes glutamine to glutamate. The samples were gathered from soil of Taxila, Wah Cantt and Quetta, Pakistan for the isolation of glutaminase producing bacteria. After primary screening, subordinate screening was done which includes multiple testification such as purification, observation of morphological characters and biochemical testing of bacterial strains along with 16S rRNA sequence homology testing. Five bacterial strains were selected showing glutaminase positive test in screening, enzyme production via fermentation and enzymatic and protein assays. Taxonomical characterization of the isolates identified them asBacillus subtilisU1,Achromobacter xylosoxidansG1,Bacillus subtilisQ2,Stenotrophomonas maltophiliaU3 andAlcaligenes faecalisS3. The optimization of different effectors such as incubation time, inducers, carbon source, pH, and nitrogen source were also put under consideration. There was slight difference among incubation of bacterial culture, overall, 36 hours of incubation time was the best for glutaminase production by all the strains. Optimal pH was around 9 inAchromobacter xylosoxidansG1 andAlcaligenes faecalisS3, pH 6 inBacillus subtilisU1, pH 8 inStenotrophomonas maltophiliaU3, pH 6-8 inBacillus subtilisQ2. Best glutaminase production was obtained at 37°C byBacillus subtilisU1andBacillus subtilisQ2, 30°C forAchromobacter xylosoxidansG1,Stenotrophomonas maltophiliaU3 and 25°C byAlcaligenes faecalisS3. The carbon sources put fluctuated effects on activity of enzyme in such a way that glucose was the best carbon source forBacillus subtilisU1andBacillus subtilisQ2, Sorbitol forAchromobacter xylosoxidansG1 andAlcaligenes faecalisS3 while xylose was the best forStenotrophomonas maltophiliaU3. Yeast extract and Trypton were among good nitrogen sources forAchromobacter xylosoxidansG1 and ofBacillus subtilisU1 respectively. Glutamine was the best inducer forBacillus subtilisQ2,Alcaligenes faecalisS3 andStenotrophomonas maltophiliaU3, while lysine forAchromobacter xylosoxidansG1 and glycine act as good inducer in case ofBacillus subtilisU1. After implementation of optimal conditions microbial L-glutaminase production can be achieved and the bacterial isolates have a great potential for production of glutaminase enzyme and their applications.