Catalytic Properties of Lipopolysaccharide (LPS) Binding Protein
Catalytic Properties of Lipopolysaccharide (LPS) Binding Protein
复制标题
脂多糖 (LPS) 结合蛋白的催化特性
DOI：
--
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发表时间：
1996
影响因子：
4.8
通讯作者：
S. Wright
中科院分区：
文献类型：
--
作者：
Bo Yu;S. Wright
脂多糖（LPS）结合蛋白（LBP）是一种脂转移蛋白，它催化LPS单体从胶束转移到可溶性CD 14（sCD 14）上的结合位点，以及LPS从LPS·sCD 14复合物转移到HDL颗粒。为了表征这两个反应中的第一个，用荧光团二氟化硼二吡咯亚甲基（BODIPY）共价衍生的LPS用于监测真实的时间内LPS的LBP催化运动。BODIPY-LPS胶束的荧光效率低，但在溶解于洗涤剂中或与sCD 14结合后强烈增加。BODIPY-LPS与sCD 14的自发结合非常缓慢，但通过亚化学计量浓度的LBP加速，并且在各种条件下测量结合速率。LBP催化的转移与sCD 14和LPS浓度均呈一级关系，表观K值分别为sCD 14 12 μg/ml和LPS 100 ng/ml。LBP的最大转换数约为150个LPS分子/LBP。LBP单独引起BODIPY-LPS的荧光的小但可测量的增加，表明其结合LPS聚集体但不容易去除LPS单体。随后加入sCD 14引起荧光大幅增加，表明BODIPY-LPS转移至sCD 14。这些和其他观察结果表明，LPS通过有序的三元复合物反应机制转移，其中LBP将LPS单体从LPS聚集体转移到sCD 14，而不从LPS聚集体解离。
Lipopolysaccharide (LPS) binding protein (LBP) is a lipid transfer protein that catalyzes transfer of LPS monomers from micelles to a binding site on soluble CD14 (sCD14) and transfer of LPS from LPS•sCD14 complexes to HDL particles. To characterize the first of these two reactions, LPS covalently derivatized with the fluorophore, boron dipyrromethene difluoride (BODIPY), was used to monitor LBP-catalyzed movement of LPS in real time. The fluorescence efficiency of micelles of BODIPY-LPS was low but was strongly increased upon dissolution in detergent or upon binding to sCD14. Spontaneous binding of BODIPY-LPS to sCD14 was very slow but was accelerated by substoichiometric concentration of LBP, and the rate of binding was measured under a variety of conditions. LBP-catalyzed transfer was first order with respect to both sCD14 and LPS concentration, and the apparent K values were 12 μg/ml for sCD14 and 100 ng/ml for LPS. The maximum turnover number for LBP was approximately 150 molecules of LPS min LBP. LBP alone caused a small but measurable increase in the fluorescence of BODIPY-LPS, suggesting that it bound LPS aggregates but did not readily remove LPS monomers. The subsequent addition of sCD14 caused a large fluorescence increase, suggesting transfer of BODIPY-LPS to sCD14. These and other observations suggest that LPS is transferred by an ordered ternary complex reaction mechanism in which LBP transfers LPS monomer from LPS aggregates to sCD14 without dissociating from the LPS aggregate.
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影响因子：
56.9
作者：
SCHUMANN, RR;LEONG, SR;ULEVITCH, RJ
通讯作者：
ULEVITCH, RJ
影响因子：
56.9
作者：
WRIGHT, SD;RAMOS, RA;MATHISON, JC
通讯作者：
MATHISON, JC
DOI：
10.1016/s0021-9258(18)81700-8
发表时间：
1989-06
期刊：
The Journal of biological chemistry
影响因子：
--
作者：
P. Tobias;K. Soldau;R. Ulevitch
通讯作者：
P. Tobias;K. Soldau;R. Ulevitch
CD14 结合脂多糖的分析。
DOI：
--
发表时间：
1993
期刊：
The Journal of biological chemistry
影响因子：
--
作者：
Kirkland,TN;Finley,F;Leturcq,D;Moriarty,A;Lee,JD;Ulevitch,RJ;Tobias,PS
通讯作者：
Tobias,PS