title: Kdo hydroxylase is an inner core assembly enzyme in the Ko-containing lipopolysaccharide biosynthesis.
abstract: The lipopolysaccharide (LPS) isolated from certain important Gram-negative pathogens including a human pathogen Yersinia pestis and opportunistic pathogens Burkholderia mallei and Burkholderia pseudomallei contains d-glycero-d-talo-oct-2-ulosonic acid (Ko), an isosteric analog of 3-deoxy-d-manno-oct-2-ulosonic acid (Kdo). Kdo 3-hydroxylase (KdoO), a Fe(2+)/α-KG/O2 dependent dioxygenase from Burkholderia ambifaria and Yersinia pestis is responsible for Ko formation with Kdo2-lipid A as a substrate, but in which stage KdoO functions during the LPS biosynthesis has not been established. Here we purify KdoO from B. ambifaria (BaKdoO) to homogeneity for the first time and characterize its substrates. BaKdoO utilizes Kdo2-lipid IVA or Kdo2-lipid A as a substrate, but not Kdo-lipid IVAin vivo as well as in vitro and Kdo-(Hep)kdo-lipid A in vitro. These data suggest that KdoO is an inner core assembly enzyme that functions after the Kdo-transferase KdtA but before the heptosyl-transferase WaaC enzyme during the Ko-containing LPS biosynthesis.
authors.affiliation: Center for Theragnosis, Korea Institute of Science and Technology, Seoul 136-791, Republic of Korea; Department of Biological Chemistry, KIST Campus, Korea University of Science and Technology (UST), Seoul 136-791, Republic of Korea. Electronic address: hschung@kist.re.kr.
authors.forename: Hak Suk
authors.initials: HS
authors.lastname: Chung
authors.affiliation: Center for Theragnosis, Korea Institute of Science and Technology, Seoul 136-791, Republic of Korea; Department of Biological Chemistry, KIST Campus, Korea University of Science and Technology (UST), Seoul 136-791, Republic of Korea.
authors.forename: Eun Gyeong
authors.initials: EG
authors.lastname: Yang
authors.affiliation: Department of Biological Chemistry, KIST Campus, Korea University of Science and Technology (UST), Seoul 136-791, Republic of Korea.
authors.forename: Dohyeon
authors.initials: D
authors.lastname: Hwang
authors.affiliation: Center for Theragnosis, Korea Institute of Science and Technology, Seoul 136-791, Republic of Korea.
authors.forename: Ji Eun
authors.initials: JE
authors.lastname: Lee
authors.affiliation: Department of Biochemistry, Duke University Medical Center, Durham, NC 27710, USA.
authors.forename: Ziqiang
authors.initials: Z
authors.lastname: Guan
authors.affiliation: Department of Biochemistry, Duke University Medical Center, Durham, NC 27710, USA.
authors.forename: Christian R H
authors.initials: CR
authors.lastname: Raetz
mesh_terms: D019117:Burkholderia / Q000235:genetics / Q000378:metabolism*; D002413:Cations, Divalent; D015870:Gene Expression; D006017:Glycolipids / Q000096:biosynthesis*; D016695:Glycosyltransferases / Q000235:genetics / Q000378:metabolism; D007501:Iron / Q000378:metabolism; D007656:Ketoglutaric Acids / Q000378:metabolism; D008050:Lipid A / Q000031:analogs & derivatives* / Q000096:biosynthesis; D008070:Lipopolysaccharides / Q000096:biosynthesis*; D006899:Mixed Function Oxygenases / Q000235:genetics / Q000378:metabolism*; D010100:Oxygen / Q000378:metabolism; D013379:Substrate Specificity; D014166:Transferases / Q000235:genetics / Q000378:metabolism
chemical_list: D002413:Cations, Divalent; D006017:Glycolipids; C506188:Kdo2-lipid A; D007656:Ketoglutaric Acids; D008050:Lipid A; D008070:Lipopolysaccharides; C040142:lipid A precursors, bacterial; D007501:Iron; D006899:Mixed Function Oxygenases; D014166:Transferases; D016695:Glycosyltransferases; C019917:3-deoxy-D-manno-octulosonate transferase; C080934:lipooligosaccharide 1,5-heptosyltransferase; D010100:Oxygen
keywords: Burkholderia LPS; Fe(2+)/O(2)/α-KG dependent dioxygenase; Kdo hydroxylase; Ko formation; LPS inner core assembly