3ejc
Full length Receptor Binding Protein from Lactococcal phage TP901-1
Structural highlights
FunctionEvolutionary Conservation Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf. Publication Abstract from PubMedP335 lactococcal phages infect the gram(+) bacterium Lactococcus lactis using a large multiprotein complex located at the distal part of the tail and termed baseplate (BP). The BP harbors the receptor-binding proteins (RBPs), which allow the specific recognition of saccharidic receptors localized on the host cell surface. We report here the electron microscopic structure of the phage TP901-1 wild-type BP as well as those of two mutants bppL (-) and bppU(-), lacking BppL (the RBPs) or both peripheral BP components (BppL and BppU), respectively. We also achieved an electron microscopic reconstruction of a partial BP complex, formed by BppU and BppL. This complex exhibits a tripod shape and is composed of nine BppLs and three BppUs. These structures, combined with light-scattering measurements, led us to propose that the TP901-1 BP harbors six tripods at its periphery, located around the central tube formed by ORF46 (Dit) hexamers, at its proximal end, and a ORF47 (Tal) trimer at its distal extremity. A total of 54 BppLs (18 RBPs) are thus available to mediate host anchoring with a large apparent avidity. TP901-1 BP exhibits an infection-ready conformation and differs strikingly from the lactococcal phage p2 BP, bearing only 6 RBPs, and which needs a conformational change to reach its activated state. The comparison of several Siphoviridae structures uncovers a close organization of their central BP core whereas striking differences occur at the periphery, leading to diverse mechanisms of host recognition. Structure and molecular assignment of lactococcal phage TP901-1 baseplate.,Bebeacua C, Bron P, Lai L, Vegge CS, Brondsted L, Spinelli S, Campanacci V, Veesler D, van Heel M, Cambillau C J Biol Chem. 2010 Dec 10;285(50):39079-86. Epub 2010 Oct 11. PMID:20937834[1] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. References
| ||||||||||||||||||
