Roles of restriction-modification gene complexes in generation of genome diversity in bacteria

A.基因组动态的实验分析。(A-1)限制-修饰基因复合体的增殖。这里我们发现限制-修饰基因复合体的扩增。插入到芽孢杆菌染色体中的BamHI基因复合物显示出对由同源DNA片段替换的抗性。增殖发生在具有DNA释放、摄取和转化的天然能力的细菌中，并且可能有助于RM基因复合物在病毒样生命周期中的传播。(A-2)限制性修饰基因复合物的基因组内移动：当我们试图将限制性修饰基因复合物从细胞中消除时，我们检测到它在细胞内的移动。从这些产品的序列测定，我们讨论了限制性修饰基因复合物，IS和宿主同源重组功能之间的潜在合作机制。(A-3)通过限制-修饰系统防御基因组的攻击。我们证明了宿主攻击 ...更多信息 通过EcoRII限制修饰基因复合物可以被Dcm单独的甲基转移酶抵消。我们还发现，染色体中的位点特异性重组机制可以保护基因组免受限制修饰系统的攻击。近缘细菌基因组的比较与信息学分析。(B-1)我们比较了两株金黄色葡萄球菌的基因组序列。金黄色。我们列出了中等大小的基因组多态性，并推断其形成机制。我们在S.人类(B-2)我们比较了两株奈瑟氏球菌的基因组序列。脑膜炎球菌和1株脑膜炎奈瑟氏球菌。淋球菌和确定的基因组重排机制有关的IS和限制修饰基因复合物。(B-3)基因组比较工具的开发。我们开发了一个用于比较密切相关基因组的工具。限制性修饰酶及其基因的一种新命名法根据限制性酶甲基转移酶及其基因的生物多样性，提出了一种新的限制性酶甲基转移酶及其基因命名法。少

A. Experimental analyses of genome dynamics.(A-1) Multiplication of a restriction-modification gene complex.Here we found amplification of a restriction-modification gene complex. BamHI gene complex inserted into Bacillus chromosome showed resistance to replacement by a homologous stretch of DNA. The multiplication takes place in a bacterium with natural capacity for DNA release, uptake and transformation and might contribute to spreading of RM gene complexes in a virus like life cycle.(A-2) Intragenomic movement of a restriction-modification gene complex.We detected movement of a restriction-modification gene complex within a cell when attempts were made to eliminate it from the cell. From sequence determination of these products, we discussed mechanisms of the underlying cooperation between restriction-modification gene complexes, IS and host homologous recombination functions.(A-3) Defense of genomes against attack by restriction-modification systems.We demonstrated that host attack … More by EcoRII restriction-modification gene complex can be counteracted by Dcm solitary methyltransferase. We also found that site-specific recombination machinery in the chromosome can defend the genome against attack by a restriction-modification system.B. Comparison and informatic analysis of closely related bacterial genomes.(B-1) Staphylococcus aureus.We compared genome sequences of two strains of S. aureus. We listed medium-sized genome polymorphisms and inferred mechanisms of their formation. We identified restriction-modification gene homologues in S. hominis.(B-2) Neisseria.We compared genomes sequences of two strains of N. meningitides and one strain of N. gonorhoeae and identified genome rearrangement mechanisms related to IS and restriction-modification gene complexes.(B-3) Development of tools for genome comparison.We developed a tool for comparison of closely-related genomes.C. A new nomenclature for restriction modification enzymes and their genes.We proposed a new system of nomenclature of restriction enzymes methyltransferases and their genes based on their biological diversity. Less