Diversity of esterase and lipase producing haloalkaliphilic bacteria from Lake Magadi in Kenya

Abstract

Lipids are hydrocarbons comprised of long‐chain fatty acids and are found in all living things. In the environment, microorganisms degrade them to obtain energy using esterases and lipases. These enzymes are nowadays used in different industrial applications. We report isolation of 24 bacteria with esteresic and lipolytic activity from Lake Magadi, Kenya. The isolates were characterised using morphological, biochemical, and molecular methods. Isolates grew at an optimum salt concentration of 5–8% (w/v), pH range of 8.0–9.0, and temperature range of 35–40°C. The isolates were positive for esterase and lipase assay as well as other extracellular enzymes. Phylogenetic analysis of the 16S ribosomal RNA gene showed that the isolates were affiliated to the genus Bacillus, Alkalibacterium, Staphylococcus, Micrococcus, Halomonas, and Alkalilimnicola. None of the bacterial isolates produced antimicrobial agents, and all of them were resistant to trimethoprim and nalidixic acid but susceptible to streptomycin, amoxillin, chloramphenicol, and cefotaxime. Growth at elevated pH, salt, and temperature is an indicator that the enzymes from these organisms could function well under haloalkaline conditions. Therefore, Lake Magadi could be a good source of isolates with the potential to produce unique biocatalysts for the biotechnology industry.

Community Structure of Nitrifying and Denitrifying Bacteria from Effluents Discharged into Lake Victoria, Kenya

“…Total microbial community DNA was isolated using the phenol-chloroform protocol as described [20]. Obtained DNA pellets were air-dried and resuspended in 30.0 µl of PCR water.…”

“…Cells for nucleic acid extraction were harvested by centrifuging 1 ml of the broth cultures. Bacterial genomic DNA was isolated using the phenol-chloroform protocol as described [20]. The 16S rRNA gene was amplified using bacterial universal primers pair 8F (5′-AG (A/G) GTT TGA TCC TGG CT-3′) and 1492R reverse, (5′-CGG CTA CCT TGT TAC GAC TT-3′) on a Sure cycler 8800 (Agilent Technologies).…”

Complete Genome Sequence of Alkalihalobacillus sp. Strain LMS39, a Haloalkaliphilic Bacterium Isolated from a Hypersaline Lake

“…Strain LMS39 was isolated from dry sediments of Lake Magadi, Kenya (1°43′–2°00′S, 36°13′–36°18′E). Sediment (0.1 g) was serially diluted, and 10 −9 and 10 −10 dilutions were spread onto basal agar medium containing peptone (2 g/L), yeast extract (0.5 g/L), K 2 HPO 4 (1 g/L), CaCl 2 ·2H 2 O (0.05 g/L), MgSO 4 ·7H 2 O (0.1 g/L), and agar (14 g/L) ( 3 ). The medium was prepared with sterile lake water and supplemented with 1% (wt/vol) cellulose.…”