1O75

Tp47, the 47-Kilodalton Lipoprotein of Treponema pallidum

Summary for 1O75

• Entry DOI: 10.2210/pdb1o75/pdb
• Descriptor: 47 KDA MEMBRANE ANTIGEN, 2,3-di-O-sulfo-alpha-D-glucopyranose-(1-6)-2,3-di-O-sulfo-alpha-D-glucopyranose, XENON, ... (4 entities in total)
• Functional Keywords: lipoproteinullntigen, penicillin-binding protein, integral membrane lipoprotein, immunogen, four-domain protein, antigen, lipoprotein
• Biological source: TREPONEMA PALLIDUM
• Cellular location: Cell inner membrane ; Lipid-anchor : P29723
• Total number of polymer chains: 2
• Total formula weight: 92648.15

Authors

Deka, R.K.,Machius, M.,Norgard, M.V.,Tomchick, D.R. (deposition date: 2002-10-23, release date: 2002-11-01, Last modification date: 2024-05-08)

Primary citation

Deka, R.K.,Machius, M.,Norgard, M.V.,Tomchick, D.R.
Crystal structure of the 47-kDa lipoprotein of Treponema pallidum reveals a novel penicillin-binding protein.
J. Biol. Chem., 277:41857-41864, 2002

PubMed Abstract: Syphilis is a complex sexually transmitted disease caused by the spirochetal bacterium Treponema pallidum. T. pallidum has remained exquisitely sensitive to penicillin, but the mode of action and lethal targets for beta-lactams are still unknown. We previously identified the T. pallidum 47-kDa lipoprotein (Tp47) as a penicillin-binding protein (PBP). Tp47 contains three hypothetical consensus motifs (SVTK, TEN, and KTG) that typically form the active center of other PBPs. Yet, in this study, mutations of key amino acids within these motifs failed to abolish the penicillin binding activity of Tp47. The crystal structure of Tp47 at a resolution of 1.95 A revealed a fold different from any other known PBP; Tp47 is predominantly beta-sheet, in contrast to the alpha/beta-fold common to other PBPs. It comprises four distinct domains: two complex beta-sheet-containing N-terminal domains and two C-terminal domains that adopt immunoglobulin-like folds. The three hypothetical PBP signature motifs do not come together to form a typical PBP active site. Furthermore, Tp47 is unusual in that it displays beta-lactamase activity (k(cat) for penicillin = 271 +/- 6 s(-1)), a feature that hindered attempts to identify the active site in Tp47 by co-crystallization and mass spectrometric techniques. Taken together, Tp47 does not fit the classical structural and mechanistic paradigms for PBPs, and thus Tp47 appears to represent a new class of PBP.

PubMed: 12196546
DOI: 10.1074/jbc.M207402200

Experimental method

X-RAY DIFFRACTION (1.95 Å)