Characterization of EST3: a metagenome-derived esterase with suitable properties for biotechnological applications

Author(s)

Maester, Thais Carvalho ^[1] ; Pereira, Mariana Rangel ^[1] ; Machado Sierra, E. G. ^[1] ; Balan, Andrea ^[2] ; de Macedo Lemos, Eliana Gertrudes ^[1]

Affiliation

^[1] So Paulo State Univ UNESP, Dept Technol, Prof Paulo Donato Castellane Highway S-N, BR-14884900 Sao Paulo - Brazil

^[2] Univ Sao Paulo, Dept Microbiol, Inst Biomed Sci 2, Sao Paulo, SP - Brazil

• Document type: Journal article
• Source: Applied Microbiology and Biotechnology; v. 100, n. 13, p. 5815-5827, JUL 2016.
• Web of Science Citations: 10

Abstract

Metagenomic libraries from diverse environments have been extensive sources of many lipases and esterases; nevertheless, most of these enzymes remain biochemically uncharacterized. We previously built a metagenomic fosmid library from a microbial consortium specialized for diesel oil degradation and tested it for lipolytic activity. In the present study, we identified the PL14.H10 clone that was subcloned and sequenced, which enabled the identification of the EST3 protein. This enzyme exhibited 74 % amino acid identity with the uncharacterized alpha/beta hydrolase from Parvibaculum lavamentivorans {[}GenBank: WP012110575.1] and was classified into lipolytic enzyme family IV. Biochemical characterization revealed that EST3 presents high activity in a wide range of temperature with highest activity from 41 to 45 A degrees C. Also, this thermostable esterase acts from mild acidic to alkaline conditions with an optimum pH of 6.0. The enzyme exhibited activity against p-nitrophenyl esters of different chain lengths and highest catalytic efficiency against p-nitrophenyl caprylate. The activity of the protein was increased in the presence of 0.5 mM of Mn+2, Li+, EDTA, and 1 % of CTAB and exhibited half of the activity in the presence of 10 % methanol and ethanol. Moreover, the homology model of EST3 was built and compared to other esterases, revealing a substrate channel that should fit a wide range of substrates. Taken together, the data presented in this work reveal the unique and interesting characteristics of EST3 that might be explored for further use in biotechnological applications. (AU)

• FAPESP's process: 11/09064-6 - Expression and structural and functional characterization of genomic sequences encoding lipolytic enzymes
• Grantee: Thaís Carvalho Maester Casanova
• Support Opportunities: Scholarships in Brazil - Doctorate
• FAPESP's process: 13/03568-8 - Functional and structural characterization of lipolytic enzymes identified in a metagenomic library of consortium specialized on diesel oil degradation
• Grantee: Eliana Gertrudes de Macedo Lemos
• Support Opportunities: Regular Research Grants