来自牛瘤胃的溶纤维丁酸弧菌的一种外切-D-半乳糖醛酸酶。

An exo-D-galacturonanase of Butyrivibrio fibrisolvens from the bovine rumen.

作者信息

Heinrichová K, Wojciechowicz M, Ziołecki A

出版信息

J Gen Microbiol. 1985 Aug;131(8):2053-8. doi: 10.1099/00221287-131-8-2053.

DOI:10.1099/00221287-131-8-2053

Abstract

An intracellular pectinolytic enzyme was isolated from a cell extract of Butyrivibrio fibrisolvens and purified. The optimum pH for enzyme activity was 5.6. The enzyme preferentially degraded de-esterified substrates by hydrolysis of monosaccharide units from the non-reducing end; the only product of degradation was D-galacturonic acid. Values of Km and Vmax for oligo- and polygalacturonates indicated that the best substrate was digalacturonic acid; oligogalacturonates containing either a saturated or a delta 4,5-unsaturated non-reducing end were both degraded. The enzyme was classified as an exo-D-galacturonanase [poly(1,4-alpha-D-galacturonide) galacturonohydrolase (EC 3.2.1.67)].

摘要

从溶纤维丁酸弧菌的细胞提取物中分离并纯化出一种细胞内果胶分解酶。该酶活性的最适pH值为5.6。该酶通过从非还原端水解单糖单元优先降解去酯化底物；降解的唯一产物是D-半乳糖醛酸。寡聚半乳糖醛酸酯和聚半乳糖醛酸酯的Km和Vmax值表明，最佳底物是二半乳糖醛酸；含有饱和或δ4,5-不饱和非还原端的寡聚半乳糖醛酸酯均被降解。该酶被归类为外切-D-半乳糖醛酸酶[聚(1,4-α-D-半乳糖醛酸)半乳糖醛酸水解酶(EC 3.2.1.67)]。