Structural relationship between the enzymatic and streptococcal binding sites of human salivary alpha-amylase.
Structural relationship between the enzymatic and streptococcal binding sites of human salivary alpha-amylase.
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人唾液α-淀粉酶的酶促和链球菌结合位点之间的结构关系。
DOI：
10.1016/s0006-291x(05)80900-3
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发表时间：
1990
影响因子：
3.1
通讯作者：
Levine,MJ
中科院分区：
文献类型：
--
作者：
Scannapieco,FA;Bhandary,K;Ramasubbu,N;Levine,MJ
以前的研究已经证明，人唾液α-淀粉酶与口腔细菌戈登链球菌特异结合。这种相互作用被淀粉和麦芽三糖等底物抑制，这表明细菌结合可能涉及淀粉酶的酶位置。实验确定了结合在细菌表面的淀粉酶是否具有酶活性。结果表明，结合的淀粉酶有一半以上具有酶活性。此外，细菌结合的淀粉酶将淀粉水解为葡萄糖，葡萄糖再被细菌代谢为乳酸。在进一步的研究中，淀粉酶的组氨酸残基被焦碳酸二乙酯选择性修饰后，在链球菌结合和酶功能中的作用被评估。DEP修饰的淀粉酶的酶结合活性和链球菌结合活性均显著降低。当DEP在麦芽三糖存在的情况下发生修饰时，这些影响被减弱。与天然酶或麦芽三糖修饰的淀粉酶相比，DEP修饰的淀粉酶的二级结构发生了明显的变化。综上所述，这些结果表明，人唾液α-淀粉酶可能具有多个细菌结合和酶活性的位点，这些位点具有结构上的相似性。
Previous studies have demonstrated that human salivary α-amylase specifically binds to the oral bacteriumStreptococcus gordonii. This interaction is inhibited by substrates such as starch and maltotriose suggesting that bacterial binding may involve the enzymatic site of amylase. Experiments were performed to determine if amylase bound to the bacterial surface possessed enzymatic activity. It was found that over one-half of the bound amylase was enzymatically active. In addition, bacterial-bound amylase hydrolyzed starch to glucose which was then metabolized to lactic acid by the bacteria. In further studies, the role of amylase's histidine residues in streptococcal binding and enzymatic function was assessed after their selective modification with diethyl pyrocarbonate. DEP-modified amylase showed a marked reduction in both enzymatic and streptococcal binding activities. These effects were diminished when DEP modification occurred in the presence of maltotriose. DEP-modified amylase had a significantly altered secondary structure when compared with native enzyme or amylase modified in the presence of maltotriose. Collectively, these results suggest that human salivary α-amylase may possess multiple sites for bacterial binding and enzymatic activity which share structural similarities.
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改良猪胰α-淀粉酶的新底物特异性
DOI：
--
发表时间：
1989
期刊：
影响因子：
--
作者：
K. Ishikawa;H. Hirata
通讯作者：
H. Hirata
获得的薄膜：特定蛋白质的免疫荧光演示。
DOI：
10.1111/j.1600-0714.1973.tb01675.x
发表时间：
1973
期刊：
Journal of oral pathology
影响因子：
--
作者：
Dag Orstavik;Frederick W. Kraus
通讯作者：
Frederick W. Kraus
淀粉酶结合作为口腔链球菌的鉴别器。
影响因子：
2.1
作者：
C.W.I. Douglas;A. Pease;R. Whiley
通讯作者：
R. Whiley
转铁蛋白中组氨酸的乙氧基甲酰化和光氧化。
影响因子：
2.9
作者：
T. Rogers;R. Gold;R. Feeney
通讯作者：
R. Feeney
α-淀粉酶与糖原限制糊精的多分子复合物。
影响因子：
4.8
作者：
A. Loyter;M. Schramm
通讯作者：
M. Schramm