Identification and Characterization of Two Novel Esterases from a Metagenomic Library

Abstract

Esterases are biocatalysts in food industry aimed for nutrition improvements, formation of flavor, and food fermentation. Two esterases EstGX1 and EstGX2 were identified based on function-based screening of a soil metagenomic cosmid library. Enzyme properties including optimum pH, optimal temperature, tolerance to organic solvents and metal ions were measured, respectively. The activity of EstGX2 could maintain about 40% after incubated at 99℃ for 55 min, and could be increased in presence of 15% ethanol. The unique properties of EstGX2, high thermostability and stability in the presence of several organic solvents, may make it a promising enzyme candidate in food industry.

Tetracycline Resistance Genes Identified from Distinct Soil Environments in China by Functional Metagenomics

“…All of the sampling sites have no known exposure to antibiotics. The construction of the Yunnan and Tibet libraries were performed following the published methods ( Brady, 2007 ; Gu et al, 2015 ). In brief, 200 g of meshed soil was used to extract the environmental DNA (eDNA).…”

“…The putative tetracycline-inactivating enzyme was expressed and purified as previously described with some modification ( Gu et al, 2015 ). Briefly, overnight culture was used to inoculate 500 ml kanamycin supplemented LB broth (50 μg/ml) (1:1000 dilution) and cultured at 37°C with shaking until the OD 600 nm value reached 0.6.…”

Metagenomic Approaches as a Tool to Unravel Promising Biocatalysts from Natural Resources: Soil and Water

“…Additionally, forest soils have a high microbial diversity due to the great accumulation of organic matter [15]. Several metagenome studies have been developed, notably in soil samples from the Amazon rainforest [152], mangrove forests [153][154][155][156][157], peat-swamp forests [158,159], beech forests [160] and chestnut groves [161], to assess microbial diversity, as well as the metabolic capacities of these communities to decompose natural biomass. A metagenome from the Eucalyptus sp.…”

Enzymes and Biocatalysis

“…Additionally, forest soils have a high microbial diversity due to the great accumulation of organic matter [15]. Several metagenome studies have been developed, notably in soil samples from the Amazon rainforest [152], mangrove forests [153][154][155][156][157], peat-swamp forests [158,159], beech forests [160] and chestnut groves [161], to assess microbial diversity, as well as the metabolic capacities of these communities to decompose natural biomass. A metagenome from the Eucalyptus sp.…”