2odl

Publication Abstract from PubMed

In pathogenic Gram-negative bacteria, many virulence factors are secreted via the two-partner secretion pathway, which consists of an exoprotein called TpsA and a cognate outer membrane translocator called TpsB. The HMW1 and HMW2 adhesins are major virulence factors in nontypeable Haemophilus influenzae and are prototype two-partner secretion pathway exoproteins. A key step in the delivery of HMW1 and HMW2 to the bacterial surface involves targeting to the HMW1B and HMW2B outer membrane translocators by an N-terminal region called the secretion domain. Here we present the crystal structure at 1.92 A of the HMW1 pro-piece (HMW1-PP), a region that contains the HMW1 secretion domain and is cleaved and released during HMW1 secretion. Structural analysis of HMW1-PP revealed a right-handed beta-helix fold containing 12 complete parallel coils and one large extra-helical domain. Comparison of HMW1-PP and the Bordetella pertussis FHA secretion domain (Fha30) reveals limited amino acid homology but shared structural features, suggesting that diverse TpsA proteins have a common structural domain required for targeting to cognate TpsB proteins. Further comparison of HMW1-PP and Fha30 structures may provide insights into the keen specificity of TpsA-TpsB interactions.

The structure of the Haemophilus influenzae HMW1 pro-piece reveals a structural domain essential for bacterial two-partner secretion.,Yeo HJ, Yokoyama T, Walkiewicz K, Kim Y, Grass S, Geme JW 3rd J Biol Chem. 2007 Oct 19;282(42):31076-84. Epub 2007 Aug 14. PMID:17699157^[1]

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.