Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
6490353 | Journal of Biotechnology | 2018 | 9 Pages |
Abstract
Autoinducers are indispensable for bacterial cell-cell communication. However, due to the reliance on culture-based techniques, few autoinducer-hydrolyzing enzymes are known. In this study, we characterized soil metagenome-derived unique enzymes capable of hydrolyzing 3-hydroxypalmitic acid methyl ester (3-OH PAME), an autoinducer of the plant pathogenic bacterium Ralstonia solanacearum. Among 146 candidate lipolytic clones from a soil metagenome library, 4 unique enzymes capable of hydrolyzing the autoinducer 3-OH PAME, termed ELP86, ELP96, ELP104, and EstDL33, were selected and characterized. Phylogenetic analysis revealed that metagenomic enzymes were novel esterase/lipase candidates as they clustered as novel subfamilies of family I, V, X, and family XI. The purified enzymes displayed various levels of hydrolytic activities towards 3-OH PAME with optimum activity at 40-50â¯Â°C and pH 7-10. Interestingly, ELP104 also displayed N-(3-oxohexanoyl)-L-homoserine lactone hydrolysis activity. Heterologous expression of the gene encoding 3-OH PAME hydrolase in R. solanacearum significantly decreased exopolysaccharide production without affecting bacterial growth. mRNA transcription analysis revealed that genes regulated by quorum-sensing, such as phcA and xpsR, were significantly down-regulated in the stationary growth phase of R. solanacearum. Therefore, metagenomic enzymes are capable of quorum-quenching by hydrolyzing the autoinducer 3-OH PAME, which could be used as a biocontrol strategy against bacterial wilt.
Keywords
RT-PCRSoil metagenomeN-acyl homoserine lactonesCpGPNPRalstonia solanacearumTTCAHLNCBIDCMEPSBSAquorum quenchingbovine serum albuminTriphenyltetrazolium chlorideDichloromethanereverse transcription PCRLuria-BertaniNational Center for Biotechnology InformationExtracellular polysaccharideGas chromatography
Related Topics
Physical Sciences and Engineering
Chemical Engineering
Bioengineering
Authors
Myung Hwan Lee, Raees Khan, Weixin Tao, Kihyuck Choi, Seung Yeup Lee, Jae Wook Lee, Eul Chul Hwang, Seon-Woo Lee,