Bacillus subtilis YhcR, a High-Molecular-Weight, Nonspecific Endonuclease with a Unique Domain Structure

AUTOR(ES)
FONTE

American Society for Microbiology

RESUMO

In a continuing effort to identify ribonucleases that may be involved in mRNA decay in Bacillus subtilis, fractionation of a protein extract from a triple-mutant strain that was missing three previously characterized 3′-to-5′ exoribonucleases (polynucleotide phosphorylase [PNPase], RNase R, and YhaM) was undertaken. These experiments revealed the presence of a high-molecular-weight nuclease encoded by the yhcR gene that was active in the presence of Ca2+ and Mn2+. YhcR is a sugar-nonspecific nuclease that cleaves endonucleolytically to yield nucleotide 3′-monophosphate products, similar to the well-characterized micrococcal nuclease of Staphylococcus aureus. YhcR appears to be located principally in the cell wall and is likely to be a substrate for a B. subtilis sortase. Zymogram analysis suggests that YhcR is the major Ca2+-activated nuclease of B. subtilis. In addition to having a unique overall domain structure, YhcR contains a hitherto unknown structural domain that we have named “NYD,” for “new YhcR domain.”

Documentos Relacionados