DNA gyrase, A subunit; A type II topoisomerase that negatively supercoils closed circular double-stranded (ds) DNA in an ATP-dependent manner to modulate DNA topology and maintain chromosomes in an underwound state. Negative supercoiling favors strand separation, and DNA replication, transcription, recombination and repair, all of which involve strand separation. Also able to catalyze the interconversion of other topological isomers of dsDNA rings, including catenanes and knotted rings. Type II topoisomerases break and join 2 DNA strands simultaneously in an ATP-dependent manner.

ATP-dependent DNA helicase, RecQ family/ UvrD/REP helicase domain protein; Identified by match to protein family HMM PF00270; match to protein family HMM PF00271; match to protein family HMM PF00580; match to protein family HMM TIGR00614.

DNA polymerase III, beta subunit; Confers DNA tethering and processivity to DNA polymerases and other proteins. Acts as a clamp, forming a ring around DNA (a reaction catalyzed by the clamp-loading complex) which diffuses in an ATP- independent manner freely and bidirectionally along dsDNA. Initially characterized for its ability to contact the catalytic subunit of DNA polymerase III (Pol III), a complex, multichain enzyme responsible for most of the replicative synthesis in bacteria; Pol III exhibits 3'-5' exonuclease proofreading activity. The beta chain is required for initiation of [...]

DNA polymerase I; In addition to polymerase activity, this DNA polymerase exhibits 5'-3' exonuclease activity; Belongs to the DNA polymerase type-A family.

Conserved hypothetical protein; Inhibits all the catalytic activities of DNA gyrase by preventing its interaction with DNA. Acts by binding directly to the C- terminal domain of GyrB, which probably disrupts DNA binding by the gyrase.

phenylalanyl-tRNA synthetase, beta subunit; Identified by similarity to SP:P07395; match to protein family HMM PF01588; match to protein family HMM PF03147; match to protein family HMM PF03483; match to protein family HMM PF03484; match to protein family HMM TIGR00472; Belongs to the phenylalanyl-tRNA synthetase beta subunit family. Type 1 subfamily.

DNA topoisomerase I; Releases the supercoiling and torsional tension of DNA, which is introduced during the DNA replication and transcription, by transiently cleaving and rejoining one strand of the DNA duplex. Introduces a single-strand break via transesterification at a target site in duplex DNA. The scissile phosphodiester is attacked by the catalytic tyrosine of the enzyme, resulting in the formation of a DNA- (5'-phosphotyrosyl)-enzyme intermediate and the expulsion of a 3'-OH DNA strand. The free DNA strand then undergoes passage around the unbroken strand, thus removing DNA supe [...]

DNA replication and repair protein RecF; The RecF protein is involved in DNA metabolism; it is required for DNA replication and normal SOS inducibility. RecF binds preferentially to single-stranded, linear DNA. It also seems to bind ATP.

DNA polymerase III, subunits gamma and tau; DNA polymerase III is a complex, multichain enzyme responsible for most of the replicative synthesis in bacteria. This DNA polymerase also exhibits 3' to 5' exonuclease activity.