A two-component Kdo hydrolase in the inner membrane of Francisella novicida.
A two-component Kdo hydrolase in the inner membrane of Francisella novicida.
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DOI：
10.1111/j.1365-2958.2010.07305.x
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发表时间：
2010-11
影响因子：
3.6
通讯作者：
Raetz CR
中科院分区：
文献类型：
--
作者：
Zhao J;Raetz CR
脂质A覆盖革兰氏阴性菌外膜的外表面。在土拉热弗朗西丝菌亚种杀新生物体中，脂质A以脂多糖（LPS）的共价连接锚或游离脂质A的形式存在。弗朗西斯菌LPS的脂质A部分通过单个2-酮基-3-脱氧-D-甘露-辛酮糖酸（Kdo）残基连接至核心结构域。F. novicida KdtA是双功能的，而F.杀novicida包含膜结合的Kdo水解酶，其去除外部Kdo单元。水解酶由两种蛋白质（KdoH1和KdoH2）组成，它们由相邻的共转录基因表达。KdoH1（与唾液酸酶相关）具有单个预测的N-末端跨膜区段。KdoH2含有7个推定的跨膜序列。当在E.杆菌活性需要同时表达两种蛋白质或在非离子去污剂存在下在体外测定条件下混合来自表达单独蛋白质的菌株的膜。在大肠在表达KdoH 1和KdoH 2的大肠杆菌中，水解酶活性定位于内膜。WBB 06是一株庚糖缺陷型E.大肠杆菌突变体，使Kdo 2-脂质A作为其唯一的LPS，积累Kdo-脂质A时，表达两种水解酶组分，和1-脱磷酸-Kdo-脂质A时，同时表达水解酶和弗朗西斯菌脂质A1-磷酸酶（LpxE）。
Lipid A coats the outer surface of the outer membrane of Gram-negative bacteria. In Francisella tularensis subspecies novicida lipid A is present either as the covalently attached anchor of lipopolysaccharide (LPS) or as free lipid A. The lipid A moiety of Francisella LPS is linked to the core domain by a single 2-keto-3-deoxy-D-manno-octulosonic acid (Kdo) residue. F. novicida KdtA is bifunctional, but F. novicida contains a membrane-bound Kdo hydrolase that removes the outer Kdo unit. The hydrolase consists of two proteins (KdoH1 and KdoH2), which are expressed from adjacent, co-transcribed genes. KdoH1 (related to sialidases) has a single predicted N-terminal transmembrane segment. KdoH2 contains 7 putative transmembrane sequences. Neither protein alone catalyzes Kdo cleavage when expressed in E. coli. Activity requires simultaneous expression of both proteins or mixing of membranes from strains expressing the individual proteins under in vitro assay conditions in the presence of non-ionic detergent. In E. coli expressing KdoH1 and KdoH2, hydrolase activity is localized in the inner membrane. WBB06, a heptose-deficient E. coli mutant that makes Kdo2-lipid A as its sole LPS, accumulates Kdo-lipid A when expressing the both hydrolase components, and 1-dephospho-Kdo-lipid A when expressing both the hydrolase and the Francisella lipid A 1-phosphatase (LpxE).
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影响因子：
4.8
作者：
Newstead, Simon L.;Potter, Jane A.;Taylor, Garry L.
通讯作者：
Taylor, Garry L.
影响因子：
4.8
作者：
Kanipes, MI;Ribeiro, AA;Raetz, CRH
通讯作者：
Raetz, CRH
影响因子：
4.8
作者：
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通讯作者：
Raetz, CRH
DOI：
10.1111/j.1432-1033.1997.00716.x
发表时间：
1997-07-15
期刊：
EUROPEAN JOURNAL OF BIOCHEMISTRY
影响因子：
--
作者：
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通讯作者：
Brade, H
DOI：
10.1073/pnas.0601838103
发表时间：
2006-09-26
影响因子：
11.1
作者：
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通讯作者：
Celli, Jean