title: Recombinant DNA-methyltransferase M1.BspACI from Bacillus psychrodurans AC: purification and properties.
abstract: A restriction-modification system from Bacillus psychrodurans AC (recognition sequence 5'-CCGC-3') comprises two DNA methyltransferases: M1.BspACI and M2.BspACI. The bspACIM1 gene was cloned in the pJW2 vector and expressed in Escherichia coli cells. High-purity M1.BspACI preparation has been obtained by chromatography on different carriers. M1.BspACI has a temperature optimum of 30°C and demonstrates maximum activity at pH 8.0. M1.BspACI modifies the first cytosine in the recognition sequence 5'-CCGC-3'. The kinetic parameters of M1.BspACI DNA methylation are as follows: K(m) for phage λ DNA is 0.053 µM and K(m) for S-adenosyl-L-methionine is 5.1 µM. The catalytic constant (k(cat)) is 0.095 min(-1).
authors.affiliation: SibEnzyme, Novosibirsk 630117, Russia. tarasovamv@sibenzyme.ru
authors.forename: M V
authors.initials: MV
authors.lastname: Tarasova
authors.forename: V V
authors.initials: VV
authors.lastname: Kuznetsov
authors.forename: N A
authors.initials: NA
authors.lastname: Netesova
authors.forename: D A
authors.initials: DA
authors.lastname: Gonchar
authors.forename: S Kh
authors.initials: SKh
authors.lastname: Degtyarev
mesh_terms: D001407:Bacillus / Q000201:enzymology*; D001426:Bacterial Proteins / Q000096:biosynthesis / Q000302:isolation & purification*; D001483:Base Sequence; D003001:Cloning, Molecular; D015254:DNA Modification Methylases / Q000096:biosynthesis / Q000302:isolation & purification*; D004279:DNA, Viral / Q000378:metabolism; D057075:Enzyme Assays; D011994:Recombinant Proteins / Q000096:biosynthesis / Q000302:isolation & purification*
chemical_list: D001426:Bacterial Proteins; D004279:DNA, Viral; D011994:Recombinant Proteins; D015254:DNA Modification Methylases