NMR structure and binding studies confirm that PA4608 from Pseudomonas aeruginosa is a PilZ domain and a c-di-GMP binding protein.
PA4608 is a 125 residue protein from Pseudomonas aeruginosa with a recent identification as a PilZ domain and putative bis-(3'-5')-cyclic dimeric guanosine monophosphate (c-di-GMP) adaptor protein that plays a role in bacterial second-messenger regulated processes. The nuclear magnetic resonance (NMR) structure of PA4608 has been determined and c-di-GMP binding has been confirmed by NMR titration studies. The monomeric core structure of PA4608 contains a six-stranded anti-parallel beta barrel flanked by three helices. Conserved surface residues among PA4608 homologs suggest the c-di-GMP binding site is at one end of the barrel and includes residues in the helices as well as in the unstructured N-terminus. Chemical shift changes in PA4608 resonances upon titration with c-di-GMP confirm binding. This evidence supports the hypothesis that proteins containing PilZ domains are the long-sought c-di-GMP adaptor proteins.
Ramelot
Theresa A
TA
Pacific Northwest National Laboratory, Biological Sciences Division, Richland, Washington 99354, USA.
Yee
Adelinda
A
Cort
John R
JR
Semesi
Anthony
A
Arrowsmith
Cheryl H
CH
Kennedy
Michael A
MA
D048868:Adaptor Proteins, Signal Transducing / Q000737:chemistry* / Q000378:metabolism; D000595:Amino Acid Sequence; D001426:Bacterial Proteins / Q000737:chemistry* / Q000378:metabolism; D001665:Binding Sites; D006152:Cyclic GMP / Q000031:analogs & derivatives* / Q000378:metabolism; D008958:Models, Molecular; D008969:Molecular Sequence Data; D019906:Nuclear Magnetic Resonance, Biomolecular; D011485:Protein Binding; D011487:Protein Conformation; D017434:Protein Structure, Tertiary; D011550:Pseudomonas aeruginosa / Q000737:chemistry*; D016415:Sequence Alignment; D017386:Sequence Homology, Amino Acid; D014734:Vibrio cholerae / Q000737:chemistry
D048868:Adaptor Proteins, Signal Transducing; D001426:Bacterial Proteins; C062025:bis(3',5')-cyclic diguanylic acid; D006152:Cyclic GMP