Yuan Cansheng, Zhao Lingling, Tong Lu, Wang Lin, Ke Zhuang, Yang Ying, He Jian
College of Rural Revitalization, Jiangsu Open University, Nanjing 210036, China.
College of Life Sciences, Nanjing Agricultural University, Nanjing 210095, China.
Microorganisms. 2023 Mar 27;11(4):854. doi: 10.3390/microorganisms11040854.
Picolinic acid (PA) is a typical mono-carboxylated pyridine derivative produced by human/animals or microorganisms which could be served as nutrients for bacteria. Most strains are pathogens causing pertussis or respiratory disease in humans and/or various animals. Previous studies indicated that strains harbor the PA degradation gene cluster. However, the degradation of PA by strains remains unknown. In this study, a reference strain of genus , RB50, was investigated. The organization of gene cluster of strain RB50 was found to be similar with that of , in which the sequence similarities of each Pic proteins are between 60% to 80% except for PicB2 (47% similarity). The 3,6-dihydroxypicolinic acid (3,6DHPA) decarboxylase gene (, designated as ) of strain RB50 was synthesized and over-expressed in BL21(DE3). The PicC showed 75% amino acid similarities against known PicC from . The purified PicC can efficiently transform 3,6DHPA to 2,5-dihydroxypyridine. The PicC exhibits optimal activities at pH 7.0, 35 °C, and the and values of PicC for 3,6DHPA were 20.41 ± 2.60 μM and 7.61 ± 0.53 S, respectively. The present study provided new insights into the biodegradation of PA by pathogens of spp.
吡啶甲酸（PA）是一种典型的单羧化吡啶衍生物，由人类/动物或微生物产生，可作为细菌的营养物质。大多数菌株是导致人类和/或各种动物患百日咳或呼吸道疾病的病原体。先前的研究表明，这些菌株含有PA降解基因簇。然而，这些菌株对PA的降解情况仍不清楚。在本研究中，对该属的一株参考菌株RB50进行了研究。发现菌株RB50的基因簇组织与该属的相似，其中除PicB2外（相似度为47%），各Pic蛋白的序列相似度在60%至80%之间。合成了菌株RB50的3,6 - 二羟基吡啶甲酸（3,6DHPA）脱羧酶基因（命名为），并在大肠杆菌BL21(DE3)中进行了过表达。PicC与已知的该属PicC的氨基酸相似度为75%。纯化后的PicC能够有效地将3,6DHPA转化为2,5 - 二羟基吡啶。PicC在pH 7.0、35℃时表现出最佳活性，其对3,6DHPA的和值分别为20.41±2.60μM和7.61±0.53 S。本研究为该属病原体对PA的生物降解提供了新的见解。
