Primary structure of the common polypeptide chainb from the multi-hemoglobin system of the hydrothermal vent tube wormRiftia pachyptila: An insight on the sulfide binding-site

Proteins: Structure, Function, and BioinformaticsVolume 29, Issue 4 p. 562-574 Research Article Primary structure of the common polypeptide chain b from the multi-hemoglobin system of the hydrothermal vent tube worm Riftia pachyptila: An insight on the sulfide binding-site F. Zal, Corresponding Author F. Zal zal@lifesci.lscf.ucsb.edu Equipe Ecophysiologie, UPMC—CNRS—INSU, Station Biologique, BP 74, 29682 Roscoff cedex, France Department of Biological Sciences and Marine Science Institute, University of California, Santa Barbara, CaliforniaDepartment of Biological Sciences and Marine Science Institute, University of California, Santa Barbara, CA 93106===Search for more papers by this authorT. Suzuki, T. Suzuki Department of Biology, Faculty of Science, Kochi University, Kochi 780, JapanSearch for more papers by this authorY. Kawasaki, Y. Kawasaki Department of Biology, Faculty of Science, Kochi University, Kochi 780, JapanSearch for more papers by this authorJ.J. Childress, J.J. Childress Department of Biological Sciences and Marine Science Institute, University of California, Santa Barbara, CaliforniaSearch for more papers by this authorF.H. Lallier, F.H. Lallier Equipe Ecophysiologie, UPMC—CNRS—INSU, Station Biologique, BP 74, 29682 Roscoff cedex, FranceSearch for more papers by this authorA. Toulmond, A. Toulmond Equipe Ecophysiologie, UPMC—CNRS—INSU, Station Biologique, BP 74, 29682 Roscoff cedex, FranceSearch for more papers by this author F. Zal, Corresponding Author F. Zal zal@lifesci.lscf.ucsb.edu Equipe Ecophysiologie, UPMC—CNRS—INSU, Station Biologique, BP 74, 29682 Roscoff cedex, France Department of Biological Sciences and Marine Science Institute, University of California, Santa Barbara, CaliforniaDepartment of Biological Sciences and Marine Science Institute, University of California, Santa Barbara, CA 93106===Search for more papers by this authorT. Suzuki, T. Suzuki Department of Biology, Faculty of Science, Kochi University, Kochi 780, JapanSearch for more papers by this authorY. Kawasaki, Y. Kawasaki Department of Biology, Faculty of Science, Kochi University, Kochi 780, JapanSearch for more papers by this authorJ.J. Childress, J.J. Childress Department of Biological Sciences and Marine Science Institute, University of California, Santa Barbara, CaliforniaSearch for more papers by this authorF.H. Lallier, F.H. Lallier Equipe Ecophysiologie, UPMC—CNRS—INSU, Station Biologique, BP 74, 29682 Roscoff cedex, FranceSearch for more papers by this authorA. Toulmond, A. Toulmond Equipe Ecophysiologie, UPMC—CNRS—INSU, Station Biologique, BP 74, 29682 Roscoff cedex, FranceSearch for more papers by this author First published: 07 December 1998 https://doi.org/10.1002/(SICI)1097-0134(199712)29:4<562::AID-PROT15>3.0.CO;2-KCitations: 28AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinked InRedditWechat Abstract The deep-sea tube worm Riftia pachyptila Jones possesses a multi-hemoglobin system with three different extracellular Hbs: two dissolved in the vascular blood, V1 (ca. 3,500 kDa) and V2 (ca. 400 kDa), and one in the coelomic fluid, C1 (ca. 400 kDa). V1 Hb consists of four heme-containing, globin chains (b–e) and four linker chains (L1–L4). V2 and C1 Hbs are exclusively built from globin chains, six for V2 (a–f) and five for C1 (a–e). The complete amino acid sequence of the isolated monomeric globin chain b, common to all Riftia Hbs, has been determined by automated Edman degradation sequencing of the peptides derived by digestion with trypsin, chymotrypsin, thermolysin, and CNBr. This polypeptide chain is composed of 144 amino acid residues, providing a Mr of 16, 135.0 Da. Moreover, the primary sequence of chain b revealed 3 Cys residues at position 4, 75, and 134. Cys-4 and Cys-134 are located at positions where an intra-chain disulfide bridge is formed in all annelid, vestimentiferan, or pogonophoran chains, but Cys-75 is located at a unique position only found in three globin chains belonging to Lamellibrachia and Oligobrachia, a vestimentiferan and a pogonophoran. In both groups, Hbs can bind sulfide reversibly to fuel the chemosynthetic process of the symbiotic bacteria they harbor. Sulfide-binding experiments performed on purified Hb fractions (i.e., V1, V2, and C1 Hbs) suggest that free Cys residues on globin chains, and the numerous Cys found in linker chains, as determined previously by ESI-MS, may be the sulfide binding-sites. Blocking the free Cys by N-ethylmaleimide, we confirmed that free cysteines were involved in sulfide-binding but did not account for the whole sulfide-binding capacity of V1 Hb. Furthermore, a phylogenetic tree was constructed from 18 globin-like chains of annelid, vetimentiferan, and pogonophoran extracellular Hbs to clarify the systematic position of tubeworms. Riftia chain b clearly belongs to the “strain A” family with 30 to 80% identity with the other sequences analyzed. Its position in the tree confirmed a close relationship between vestimentiferan, pogonophoran, and annelid Hbs. Proteins 29:562–574, 1997. © 1997 Wiley-Liss, Inc. Citing Literature Volume29, Issue4December 1997Pages 562-574 RelatedInformation