title: Elevated level of the second messenger c-di-GMP in Comamonas testosteroni enhances biofilm formation and biofilm-based biodegradation of 3-chloroaniline.
abstract: The bis-(3'-5')-cyclic dimeric guanosine monophosphate (c-di-GMP) is a ubiquitous second messenger that determines bacterial lifestyle between the planktonic and biofilm modes of life. Although the role of c-di-GMP signaling in biofilm development and dispersal has been extensively studied, how c-di-GMP signaling influences environmental bioprocess activities such as biodegradation remains unexplored. To elucidate the impacts of elevating c-di-GMP level on environmental bioprocesses, we constructed a Comamonas testosteroni strain constitutively expressing a c-di-GMP synthase YedQ from Escherichia coli and examined its capability in biofilm formation and biodegradation of 3-chloroaniline (3-CA). The high c-di-GMP strain exhibited an increased binding to Congo red dye, a decreased motility, and an enhanced biofilm formation capability. In planktonic cultures, the strain with an elevated c-di-GMP concentration and the wild type could degrade 3-CA comparably well. However, under batch growth conditions with a high surface to volume ratio, an elevated c-di-GMP concentration in C. testosteroni significantly increased the contribution of biofilms in 3-CA biodegradation. In continuous submerged biofilm reactors, C. testosteroni with an elevated c-di-GMP level exhibited an enhanced 3-CA biodegradation and a decreased cell detachment rate. Taken together, this study provides a novel strategy to enhance biofilm-based biodegradation of toxic xenobiotic compounds through manipulating bacterial c-di-GMP signaling.
authors.affiliation: School of Civil and Environmental Engineering, Nanyang Technological University, Singapore, Singapore.
authors.forename: Yichao
authors.initials: Y
authors.lastname: Wu
authors.forename: Yuanzhao
authors.initials: Y
authors.lastname: Ding
authors.forename: Yehuda
authors.initials: Y
authors.lastname: Cohen
authors.forename: Bin
authors.initials: B
authors.lastname: Cao
mesh_terms: D000814:Aniline Compounds / Q000378:metabolism*; D018441:Biofilms / Q000254:growth & development*; D019149:Bioreactors / Q000382:microbiology; D001711:Biotransformation; D020604:Comamonas testosteroni / Q000235:genetics / Q000254:growth & development / Q000378:metabolism / Q000502:physiology*; D006152:Cyclic GMP / Q000031:analogs & derivatives* / Q000378:metabolism; D004926:Escherichia coli / Q000201:enzymology / Q000235:genetics; D029968:Escherichia coli Proteins / Q000235:genetics / Q000378:metabolism; D015870:Gene Expression; D019761:Phosphorus-Oxygen Lyases / Q000235:genetics / Q000378:metabolism; D011994:Recombinant Proteins / Q000235:genetics / Q000378:metabolism; D015290:Second Messenger Systems
chemical_list: D000814:Aniline Compounds; D029968:Escherichia coli Proteins; D011994:Recombinant Proteins; C062025:bis(3',5')-cyclic diguanylic acid; C031392:3-chloroaniline; D019761:Phosphorus-Oxygen Lyases; C060720:diguanylate cyclase; D006152:Cyclic GMP