Structural Determinants of the Specific Activities of an L-Amino Acid Oxidase from Pseudoalteromonas luteoviolacea CPMOR-1 with Broad Substrate Specificity.
Structural Determinants of the Specific Activities of an L-Amino Acid Oxidase from Pseudoalteromonas luteoviolacea CPMOR-1 with Broad Substrate Specificity.
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DOI：
10.3390/molecules27154726
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发表时间：
2022-07-24
期刊：
影响因子：
4.6
通讯作者：
Davidson, Victor L.
中科院分区：
文献类型：
--
作者：
Mamounis, Kyle J.;Nogueira, Maria Luiza Caldas;Salvador, Daniela Priscila Marchi;Andreo-Vidal, Andres;Sanchez-Amat, Antonio;Davidson, Victor L.
黄紫假交替单胞菌菌株CPMOR-1表达具有广泛底物特异性的黄素腺嘌呤二核苷酸（FAD）依赖性L-氨基酸氧化酶（LAAO）。稳态动力学分析其对20种蛋白质氨基酸的反应性显示出一定的活性，除脯氨酸。氨基酸底物的相对比活性不仅与Km或kcat值相关，因为这两个参数通常彼此独立地变化。Km的变化归因于不同的结合亲和力。kcat的变化归因于结合底物相对于FAD的差异定位，其降低了反应速率。这种LAAO的结构模型进行了比较与其他FAD依赖LAAO的结构，具有不同的底物特异性：LAAO蛇毒，喜欢芳香族氨基酸底物和真菌LAAO是特异性的赖氨酸。虽然这些LAAO的氨基酸序列不是非常相似，但它们的整体结构是相当的。对特定氨基酸的差异活性与这些LAAO活性位点中的特定残基相关。活性位点中与连接至底物氨基酸的α-碳的氨基和羧基相互作用的残基在所有LAAO中是保守的。与氨基酸底物的侧链相互作用的残基显示变异。这提供了深入了解的LAAO的结构决定因素，决定他们不同的底物偏好。这些结果对于利用这些酶在生物技术中的可能应用（例如去外消旋化）是有意义的。
The Pseudoalteromonas luteoviolacea strain CPMOR-1 expresses a flavin adenine dinucleotide (FAD)-dependent L-amino acid oxidase (LAAO) with broad substrate specificity. Steady-state kinetic analysis of its reactivity towards the 20 proteinogenic amino acids showed some activity to all except proline. The relative specific activity for amino acid substrates was not correlated only with Km or kcat values, since the two parameters often varied independently of each other. Variation in Km was attributed to the differential binding affinity. Variation in kcat was attributed to differential positioning of the bound substrate relative to FAD that decreased the reaction rate. A structural model of this LAAO was compared with structures of other FAD-dependent LAAOs that have different substrate specificities: an LAAO from snake venom that prefers aromatic amino acid substrates and a fungal LAAO that is specific for lysine. While the amino acid sequences of these LAAOs are not very similar, their overall structures are comparable. The differential activity towards specific amino acids was correlated with specific residues in the active sites of these LAAOs. Residues in the active site that interact with the amino and carboxyl groups attached to the α-carbon of the substrate amino acid are conserved in all of the LAAOs. Residues that interact with the side chains of the amino acid substrates show variation. This provides insight into the structural determinants of the LAAOs that dictate their different substrate preferences. These results are of interest for harnessing these enzymes for possible applications in biotechnology, such as deracemization.
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影响因子：
5.6
作者：
Moustafa, Ibrahim M.;Foster, Scoff;Vrielink, Alice
通讯作者：
Vrielink, Alice
影响因子：
3.7
作者：
Yu Z;Wang J;Lin J;Zhao M;Qiu J
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DOI：
10.1111/j.1432-1033.1993.tb17953.x
发表时间：
1993-06-01
期刊：
EUROPEAN JOURNAL OF BIOCHEMISTRY
影响因子：
--
作者：
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通讯作者：
CHRISTEN, P
影响因子：
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作者：
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通讯作者：
Schomburg, Dietmar
影响因子：
3.5
作者：
Ehara, T;Kitajima, S;Tsuchiya, T
通讯作者：
Tsuchiya, T