title: Cyclic di-GMP: a second messenger required for long-term survival, but not for biofilm formation, in Mycobacterium smegmatis.
abstract: Cyclic di-GMP (c-di-GMP) plays an important role in bacterial adaptation to enable survival in changing environments. It orchestrates various pathways involved in biofilm formation, changes in the cell surface, host colonization and virulence. In this article, we report the presence of c-di-GMP in Mycobacterium smegmatis, and its role in the long-term survival of the organism. M. smegmatis has a single bifunctional protein with both GGDEF and EAL domains, which show diguanylate cyclase (DGC) and phosphodiesterase (PDE)-A activity, respectively, in vitro. We named this protein MSDGC-1. Deletion of the gene encoding MSDGC-1 did not affect growth and biofilm formation in M. smegmatis, but long-term survival under conditions of nutritional starvation was affected. Most of the proteins that contain GGDEF and EAL domains have been demonstrated to have either DGC or PDE-A activity. To gain further insight into the regulation of the protein, we cloned the individual domains, and tested their respective activities. MSDGC-1, the full-length protein, is required for activity, as its GGDEF and EAL domains are inactive when separated.
authors.affiliation: Molecular Biophysics Unit, Indian Institute of Science, Bangalore 560012, India.
authors.forename: Manish
authors.initials: M
authors.lastname: Kumar
authors.affiliation: Molecular Biophysics Unit, Indian Institute of Science, Bangalore 560012, India.
authors.forename: Dipankar
authors.initials: D
authors.lastname: Chatterji
mesh_terms: D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism*; D018441:Biofilms / Q000254:growth & development*; D003001:Cloning, Molecular; D006152:Cyclic GMP / Q000031:analogs & derivatives* / Q000378:metabolism; D004926:Escherichia coli / Q000235:genetics / Q000254:growth & development; D029968:Escherichia coli Proteins; D017353:Gene Deletion; D015870:Gene Expression; D018390:Gene Targeting; D050296:Microbial Viability; D020102:Mycobacterium smegmatis / Q000235:genetics / Q000254:growth & development*; D010727:Phosphoric Diester Hydrolases / Q000235:genetics / Q000378:metabolism; D019761:Phosphorus-Oxygen Lyases / Q000235:genetics / Q000378:metabolism; D015290:Second Messenger Systems
chemical_list: D001426:Bacterial Proteins; D029968:Escherichia coli Proteins; C062025:bis(3',5')-cyclic diguanylic acid; D010727:Phosphoric Diester Hydrolases; D019761:Phosphorus-Oxygen Lyases; C060720:diguanylate cyclase; D006152:Cyclic GMP