Environmental Biotechnology Section, Indian Institute of Toxicology Research (Council of Scientific and Industrial Research), Mahatma Gandhi Marg, Lucknow, 226001, India.
Appl Biochem Biotechnol. 2013 Feb;169(4):1397-404. doi: 10.1007/s12010-012-0035-8. Epub 2013 Jan 12.
Enzyme "hexachlorocyclohexane (HCH) dehydrochlorinase LinA" mediates first step of aerobic microbial degradation of a chlorinated insecticide γ-HCH. The archetypal LinA-type1 consists of 156 amino acids that include a directly repeated hexapeptide motif GIHFAP at positions 141-146 and 148-153. Analysis of a series of LinA mutants, containing none, one, two, or three units of this repeated motif revealed that two units, as present in wild-type LinA, are required for its optimal activity and stability. Moreover, the presence of a bend in its secondary structure due to a proline residue that precedes the distal repeated unit contributes to enhanced LinA activity.
酶“六氯环己烷（HCH）脱氯化氢酶 LinA”介导了氯化杀虫剂γ-HCH 的需氧微生物降解的第一步。典型的 LinA 型 1 由 156 个氨基酸组成，其中包括位于位置 141-146 和 148-153 的直接重复六肽基序 GIHFAP。对一系列 LinA 突变体的分析，这些突变体不含、含一个、两个或三个重复基序单位，结果表明，野生型 LinA 中存在的两个单位是其最佳活性和稳定性所必需的。此外，由于位于远侧重复单元之前的脯氨酸残基，其二级结构中存在一个弯曲，这有助于提高 LinA 的活性。
