TY - JOUR
T1 - Crystal Structure of the 16 Heme Cytochrome from Desulfovibrio gigas
T2 - A Glycosylated Protein in a Sulphate-reducing Bacterium
AU - Santos-Silva, Teresa
AU - Dias, João Miguel
AU - Dolla, Alain
AU - Durand, Marie Claire
AU - Gonçalves, Luísa L.
AU - Lampreia, Jorge
AU - Moura, Isabel
AU - Romão, Maria João
N1 - Funding Information:
This work was supported by IHP-Contract HPRI-CT-1999-00040/2001-00140 of the European Commission and by Fundação para a Ciência e Tecnologia, SFRH/BD/6358/2001 to T.S.S. and SFRH/BPD/7136/2001 to J.M.D. The authors thank Dr Gleb Bourenkov and Dr Hans Bartunik, from the Max-Planck Research Unit for Structural Molecular Biology, MPG-ASMB c/o DESY, Hamburg for data collection and Dr Ana Coelho from Instituto de Tecnologia Química e Biológica, Oeiras, Portugal for mass spectrometry analysis. The authors thank Dr Carlos Salgueiro for critical reading of the manuscript and helpful suggestions.
PY - 2007/7/20
Y1 - 2007/7/20
N2 - Sulphate-reducing bacteria have a wide variety of periplasmic cytochromes involved in electron transfer from the periplasm to the cytoplasm. HmcA is a high molecular mass cytochrome of 550 amino acid residues that harbours 16 c-type heme groups. We report the crystal structure of HmcA isolated from the periplasm of Desulfovibrio gigas. Crystals were grown using polyethylene glycol 8K and zinc acetate, and diffracted beyond 2.1 Å resolution. A multiple-wavelength anomalous dispersion experiment at the iron absorption edge enabled us to obtain good-quality phases for structure solution and model building. DgHmcA has a V-shape architecture, already observed in HmcA isolated from Desulfovibrio vulgaris Hildenborough. The presence of an oligosaccharide molecule covalently bound to an Asn residue was observed in the electron density maps of DgHmcA and confirmed by mass spectrometry. Three modified monosaccharides appear at the highly hydrophobic vertex, possibly acting as an anchor of the protein to the cytoplasmic membrane.
AB - Sulphate-reducing bacteria have a wide variety of periplasmic cytochromes involved in electron transfer from the periplasm to the cytoplasm. HmcA is a high molecular mass cytochrome of 550 amino acid residues that harbours 16 c-type heme groups. We report the crystal structure of HmcA isolated from the periplasm of Desulfovibrio gigas. Crystals were grown using polyethylene glycol 8K and zinc acetate, and diffracted beyond 2.1 Å resolution. A multiple-wavelength anomalous dispersion experiment at the iron absorption edge enabled us to obtain good-quality phases for structure solution and model building. DgHmcA has a V-shape architecture, already observed in HmcA isolated from Desulfovibrio vulgaris Hildenborough. The presence of an oligosaccharide molecule covalently bound to an Asn residue was observed in the electron density maps of DgHmcA and confirmed by mass spectrometry. Three modified monosaccharides appear at the highly hydrophobic vertex, possibly acting as an anchor of the protein to the cytoplasmic membrane.
KW - MAD
KW - heme c
KW - high molecular weight cytochrome
KW - protein glycosylation
KW - sulphate reduction bacteria
UR - http://www.scopus.com/inward/record.url?scp=34249950618&partnerID=8YFLogxK
U2 - 10.1016/j.jmb.2007.04.055
DO - 10.1016/j.jmb.2007.04.055
M3 - Article
C2 - 17531266
AN - SCOPUS:34249950618
SN - 0022-2836
VL - 370
SP - 659
EP - 673
JO - Journal of Molecular Biology
JF - Journal of Molecular Biology
IS - 4
ER -