The transformation frequency of plasmids into Bacillus anthracis is affected by adenine methylation.

摘要: Abstract Plasmids pLTV1 and pHV33, capable of replicating in both Gram+ Gram- bacterial hosts (shuttle vectors), when derived from the Escherichia coli strain HB101, were inactive an electro-transformation assay employing Bacillus anthracis strains ΔAmes-1 ΔV1B-1 as recipients. The same plasmids isolated DNA methyltransferase (MTase)-deficient E. GM2929 (dam, dcm), able to transform B. at a frequency 102–103 transformants/μg plasmid DNA. Efficient transformation was also obtained propagated subtilis 168 (102–104 DNA). used are known harbor restriction/modification systems that recognize cytosine target for methylation. In contrast, no adenine methylation activities have been reported these strains. data presented indicate containing methylated residues is restricted studied here, resulting decreased DNA-mediated frequencies. This inhibition could be alleviated by propagating species MTase-deficient (dam) or 168, before their introduction into