Production, Purification and Partial Characterization of Four Lipases from a Thermophile Isolated from Deception Island

Abstract

Four lipases were purified from ID17, a thermophilic bacterium belonging to Geobacillus genus isolated from Deception Island, Antarctica. Lipase activity was detected by opacity test and p‐nitrophenyl laurate methods. Lipase production was better in a medium containing tryptone as the carbon and nitrogen source, without non‐ionic detergents and pH 7.5. Proteins were ultrafiltered from supernatant and separated using anion exchange and size exclusion chromatography resulting in four distinct fractions with lipase activity (called Lip1–4). Purified lipases showed an optimal pH at 9.0, 9.5, 10.0 and 8.0 and temperature at 65, 70, 75 and 80 °C for Lip1–4, respectively. Lip1 and Lip2 showed higher activity using p‐nitrophenol decanoate as substrate, whereas Lip3 and Lip4 prefer p‐nitrophenol laurate. Based on their molecular weight Lip1 and Lip2 are trimeric and pentameric proteins, respectively, whereas Lip3 and Lip4 are monomeric proteins. Lip1 was exceptionally thermostable maintaining 70 % of its activity after incubating it at 70 °C for 8 h. Based on their characteristics, the four lipases obtained from ID17 are good candidates to understand the mechanisms of lipase stability and to be used in different types of industrial applications.

Polyphasic Analysis Reveals Potential Petroleum Hydrocarbon Degradation and Biosurfactant Production by Rare Biosphere Thermophilic Bacteria From Deception Island, an Active Antarctic Volcano

“…To date, only a few studies have attempted to isolate thermophilic microorganisms from Deception Island for potential use in industrial processes. Cultured bacterial isolates belonging to Geobacillus, Bacillus, Brevibacillus , and Thermus were explored and showed positives results for the production of lipases ( Muñoz et al, 2013 , 2015 ). Flores et al (2018) partially characterized a thermophilic microorganism identified as Bacillus gelatini , which showed stable glutamate dehydrogenase activity at high temperatures.…”

Isolation and characterization of a novel laccase from an Antarctic thermophilic Geobacillus

“…The isolate was found to be a thermophilic, aerobic, Gram-positive bacterium classified according to molecular criteria as a member of the Geobacillus genus. In a previous work (Muñoz et al 2013), its optimal growth conditions were found at pH values between 5.5 and 8.0 and at temperatures between 50°C and 70°C. Bacteria were grown in a modified marine media loosely based on Bacto Marine Broth (DIFCO 2216).…”

“…ID17. This microorganism was isolated from a hot spring found on Deception Island, Antarctica (Muñoz et al 2013). The laccase activity was detected using syringaldazine (SGZ) as a substrate.…”