4.7 Article

Characterization of 5′-nucleotidases secreted from Streptomyces

期刊

APPLIED MICROBIOLOGY AND BIOTECHNOLOGY
卷 107, 期 7-8, 页码 2289-2302

出版社

SPRINGER
DOI: 10.1007/s00253-023-12426-2

关键词

Bacterial 5 '-nucleotidase; Streptomyces; Secretion; Phosphorus; Adaptive response

向作者/读者索取更多资源

In this study, two Streptomyces strains (NE5-10 and Y2F8-2) exhibiting 5'-inosine monophosphate (IMP)-dephosphorylating activity were obtained from soil isolates. The responsible enzyme was purified and the coding sequence was identified in the whole genome sequence of each strain. Phylogenetic analysis showed that the isolated Streptomyces enzymes represent a novel group of bacterial 5'-nucleotidases. Enzymatic characterization revealed differences in optimal temperature and pH, dependence on divalent cations, and substrate specificity between the two Streptomyces enzymes.
To study the ability of Streptomyces to utilize environmental nucleotides, we screened for strains exhibiting extracellular 5 '-inosine monophosphate (IMP)-dephosphorylating activity in our collection of soil isolates and obtained two producers: NE5-10 and Y2F8-2. The enzyme responsible for the activity was purified from the culture supernatant of each strain, and its mass spectral data were used to identify the coding sequence. The gene was successfully identified in the whole genome sequence of each strain; it was located in a conserved gene cluster of phosphate-related functions and encoded an approximately 600-amino acid long protein containing an N-terminal secretion signal. The mature part of the protein exhibited similarity to a known bacterial 5 '-nucleotidase. The locus of the 5 '-nucleotidase gene contained genes encoding proteins involved in phosphate utilization. The conserved gene arrangement of the locus in various Streptomyces genomes suggested the genetic region to be involved in phosphate-scavenging in this group of bacteria. Phylogenetic analysis demonstrated that the isolated Streptomyces enzymes represent an uncharacterized group of bacterial 5 '-nucleotidases. Enzymatic characterization of the two Streptomyces enzymes demonstrated that both enzymes exhibited 5 '-nucleotidase activity but differed in terms of optimal temperature and pH, dependence on divalent cations, and substrate specificity. The Km and Vmax values of the 5 '-IMP-dephosphorylating activity were 0.239 mM and 9.47 U/mg, respectively, for NE5-10 and 0.221 mM and 38.17 U/mg, respectively, for Y2F8-2. Enzyme activity in the culture broth of the two Streptomyces producers occurred in a phosphate-limitation-dependent manner, supporting their involvement in the acquisition of phosphorus.

作者

我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。

评论

主要评分

4.7
评分不足

次要评分

新颖性
-
重要性
-
科学严谨性
-
评价这篇论文

推荐

暂无数据
暂无数据