Phospholipase activity of Helicobacter pylori and its inhibition by bismuth salts. Biochemical and biophysical studies.
Phospholipase activity of Helicobacter pylori and its inhibition by bismuth salts. Biochemical and biophysical studies.
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幽门螺杆菌的磷脂酶活性及其对铋盐的抑制作用。
DOI：
10.1007/bf01297087
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发表时间：
1993
影响因子：
3.1
通讯作者：
Lichtenberger,LM
中科院分区：
文献类型：
--
作者：
Ottlecz,A;Romero,JJ;Hazell,SL;Graham,DY;Lichtenberger,LM
在这项研究中，我们测量了胃炎诱发细菌幽门螺杆菌的培养基滤液和法式压榨裂解物的磷脂酶 A (PLA) 和 C (PLC) 活性。我们在此报告，两者H.幽门裂解液和滤液含有 PLA1、PLA2 和 C 酶，它们分别容易水解放射性标记的二棕榈酰磷脂酰胆碱 (DPPC) 和磷酰胆碱底物。 PLA 和 C 酶的比活性分别在 6.5-7.0 和 8.4-8.8 pH 范围内最大。胶体次柠檬酸铋 (CBS) 对 PLA2 和 H 的 C 活性产生剂量依赖性抑制。幽门裂解物和滤液。通过向孵育混合物中添加 CaCl2，CBS 对 PLA2 的这种抑制作用以剂量依赖性方式被拮抗，这表明钙和铋可能会竞争酶上的同一位点。相反，铋盐抑制H的PLC活性的能力。幽门裂解物不被 CaCl2 拮抗。采用表面润湿性生物物理测定系统，确定H.幽门裂解物能够以剂量依赖的方式从玻璃上去除合成磷脂单层。在铋盐的存在下，细菌裂解物催化疏水表面转变为可润湿状态的能力显着减弱。因此，我们的实验结果与 H.幽门定植通过侵蚀胃粘液凝胶表面的磷脂衬里（可能是单层）来损害胃对酸的屏障，并且该过程因铋疗法而被阻断。
In this study we measured phospholipase A (PLA) and C (PLC) activity of media filtrates and French Press lysates of the gastritis-inducing bacteriaHelicobacter pylori. We report here that bothH. pylorilysates and filtrates contain PLA1, PLA2, and C enzymes, which readily hydrolyze a radiolabeled dipalmitoylphosphatidylcholine (DPPC) and phosphorylcholine substrates, respectively. The specific activity of both PLA and C enzymes were greatest in the 6.5–7.0 and 8.4–8.8 pH ranges, respectively. Colloidal bismuth subcitrate (CBS) induced a dose-dependent inhibition of PLA2and C activity of bothH. pylorilysates and filtrates. This inhibitory effect of CBS on PLA2was antagonized in a dose-dependent fashion by the addition of CaCl2to the incubation mixture, suggesting that calcium and bismuth may be competing for the same site on the enzyme. In contrast, the ability of bismuth salts to inhibit PLC activity ofH. pylorilysates was not antagonized by CaCl2. Employing a biophysical assay system for surface wettability, it was determined thatH. pylorilysates had the capacity to remove a synthetic phospholipid monolayer off a glass in a dose-dependent fashion. This ability of the bacterial lysates to catalyze the transformation of a hydrophobic surface to a wettable state was significantly attenuated in the presence of bismuth salts. Our experimental results are, therefore, consistent with the possibility thatH. pyloricolonization compromises the stomach's barrier to acid by eroding a phospholipid lining, possibly a monolayer, on the surface of the gastric mucus gel and that this process is blocked in response to bismuth therapy.
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幽门弯曲杆菌的故事。
DOI：
10.3109/00365528809099131
发表时间：
1988
期刊：
Scandinavian journal of gastroenterology. Supplement
影响因子：
--
作者：
Barry J. Marshall
通讯作者：
Barry J. Marshall
影响因子：
1.9
作者：
L. Andersen;S. Holck;C. Povlsen;L. Elsborg;T. Justesen
通讯作者：
T. Justesen
影响因子：
6.4
作者：
BUCK, GE;GOURLEY, WK;DINUZZO, AR
通讯作者：
DINUZZO, AR
影响因子：
168.9
作者：
RAUWS, EAJ;TYTGAT, GNJ
通讯作者：
TYTGAT, GNJ
影响因子：
56.9
作者：
LICHTENBERGER, LM;GRAZIANI, LA;HILLS, BA
通讯作者：
HILLS, BA