Autotransporter domain-dependent enzymatic analysis of a novel extremely thermostable carboxylesterase with high biodegradability towards pyrethroid pesticides

Abstract

The EstPS1 gene, which encodes a novel carboxylesterase of Pseudomonas synxantha PS1 isolated from oil well-produced water, was cloned and sequenced. EstPS1 has an open reading frame of 1923 bp and encodes the 640-amino acid carboxylesterase (EstPS1), which contains an autotransporter (AT) domain (357–640 amino acids). Homology analysis revealed that EstPS1 shared the highest identity (88%) with EstA from Pseudomonas fluorescens A506 (NCBI database) and belonged to the carboxylesterase family (EC 3.1.1.1). The optimum pH and temperature of recombinant EstPS1 were found to be 8.0 and 60 °C, respectively. EstPS1 showed high thermostability, and the half-lives (T1/2 thermal inactivation) at 60, 70, 80, 90, and 100 °C were 14 h, 2 h, 31 min, 10 min, and 1 min, respectively. To understand the role of the AT domain in carboxylesterase, AT domain-truncated carboxylesterase (EstPS1ΔAT) was generated. EstPS1ΔAT showed a clearly decreased secretion rate, owing to the AT domain strongly improved secretory expression in the heterogeneous system. EstPS1 degraded various pyrethroid pesticides, and hydrolysis efficiencies were dependent on the pyrethroid molecular structure. EstPS1 degraded all the tested pyrethroid pesticides and hydrolysed the p-nitrophenyl esters of medium-short-chain fatty acids, indicating that EstPS1 is an esterase with broad specificity.

Compartmentalization of the Carbaryl Degradation Pathway: Molecular Characterization of Inducible Periplasmic Carbaryl Hydrolase from Pseudomonas spp

“…These findings suggest that the smaller Sp in CH from strain C5pp probably is assisted by the Tmd to allow successful anchoring and translocation of the polypeptide across the inner membrane. The Sp region has been reported to contribute toward activity and stability of esterases of the GDSL family (37). This was recently observed for carboxyl esterase (EstPS1), where the presence of Sp yielded a soluble and active enzyme, while EstPS1ΔSp protein was insoluble (37).…”

“…The Sp region has been reported to contribute toward activity and stability of esterases of the GDSL family (37). This was recently observed for carboxyl esterase (EstPS1), where the presence of Sp yielded a soluble and active enzyme, while EstPS1ΔSp protein was insoluble (37).…”

Cloning and characterization of a pyrethroid pesticide decomposing esterase gene, Est3385, from Rhodopseudomonas palustris PSB-S

“…Taken together, a new pyrethroid decomposing enzyme has been identified and cloned in this study. The novelty of this newly identified protein is its lack of the conserved pentapeptide motif, Gly-X-Ser-X-Gly, and AT domain 29 , found in other pyrethroids degrading enzymes (Table S1 ). Utilizing fenpropathrin as asubstrate, we have demonstrated that this novel enzyme is thermostable and can tolerate a wide range pH conditions.…”

Whole Genome Sequencing and Analysis of Fenvalerate Degrading Bacteria Citrobacter freundii CD-9

“…However, only a few studies have been carried out on microbially produced degradative enzymes and genes. The key degradation enzymes (oxygenases, carboxylesterases, and aminopeptidases) in the microbial degradation of pyrethroids have been puri ed and characterized (Chen et al 2013;Cai et al 2017;Tang et al 2017). By isolating and characterizing these functional enzymes, detailed mechanisms of microbial degradation can be determined and pyrethroid-contaminated environments can be bioremediated (Hu et al 2019).…”