MspGI Restriction–Modification System and Its Flanking Genes of Microbacterium sp. Gd 4-13

Bacteria have defense systems against the penetration of foreign DNA (phages and plasmids). Some defense systems protect bacteria from phage penetration into the cell, while others block phage replication. Antiphage defense systems are often located next to already known defense systems (RM system, CRISP-Cas system, and others). In this work, the genetic sequence flanking the restriction–modification system of Microbacterium sp. strain Gd 4-13 was analyzed. The genes of the endonuclease HNH, hypothetical proteins, recombinase, and helicase/ATPase have been identified. Their combination and some analogy with the DISARM, BREX, and Druantia systems allow us to hypothesize that, next to the MspGI restriction–modification system, there is another defense system, and together they create an island of antiphage defense in the bacteria in vivo.