I 型 HsdM 甲基转移酶的独特甲基化模式为铜绿假单胞菌 PAO1 基因组中的 DpnI 稀有切割位点做准备。

A unique methylation pattern by a type I HsdM methyltransferase prepares for DpnI rare cutting sites in the Pseudomonas aeruginosa PAO1 genome.

机构信息

Clinical research Group 'Pseudomonas Genomics', OE 6710, Hannover Medical School, Carl-Neuberg-Straße 1, 30625 Hannover, Lower Saxony, Germany.

Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet, Nobels väg 16, S-171 77 Stockholm, Sweden.

出版信息

FEMS Microbiol Lett. 2019 Mar 1;366(5). doi: 10.1093/femsle/fnz053.

DOI:10.1093/femsle/fnz053

PMID:30865771

Abstract

A physical genome map of Pseudomonas aeruginosa PAO1 had been constructed in the late 1980s by combinatorial SpeI/DpnI long-range restriction mapping. Whereas SpeI was known to cleave within the infrequent 5'-ACTAGT hexanucleotide, the rare recognition site 5'-Gm6ATC for the methylation-sensitive 4-cutter DpnI in the PAO1 genome remained elusive. Resequencing the PAO1 genome with the methylation-sensitive Single Molecule Real-Time (SMRT) sequencing technology identified DpnI to cleave the PAO1 genome at 15 palindromic GAC(N)6Gm6ATC(N)6GTC recognition sites with the central Gm6ATC palindrome to be methylated on both strands by the clone PAO1-specific type I HsdM superfamily methyltransferase M.PaePAOI (PA2735).

摘要

20 世纪 80 年代末，通过组合 SpeI/DpnI 长距离限制图谱构建了铜绿假单胞菌 PAO1 的物理基因组图谱。虽然已知 SpeI 在不常见的 5'-ACTAGT 六核苷酸内切割，但在 PAO1 基因组中，甲基化敏感的 4 切割酶 DpnI 的罕见识别位点 5'-Gm6ATC 仍然难以捉摸。用甲基化敏感的单分子实时（SMRT）测序技术重新测序 PAO1 基因组，鉴定出 DpnI 在 15 个回文 GAC（N）6Gm6ATC（N）6GTC 识别位点切割 PAO1 基因组，其中中央 Gm6ATC 回文序列由克隆 PAO1 特异性 I 型 HsdM 超家族甲基转移酶 M.PaePAOI（PA2735）在两条链上甲基化。