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Diverse functions of restriction-modification systems in addition to cellular defense.

ABSTRACT: Restriction-modification (R-M) systems are ubiquitous and are often considered primitive immune systems in bacteria. Their diversity and prevalence across the prokaryotic kingdom are an indication of their success as a defense mechanism against invading genomes. However, their cellular defense function does not adequately explain the basis for their immaculate specificity in sequence recognition and nonuniform distribution, ranging from none to too many, in diverse species. The present review deals with new developments which provide insights into the roles of these enzymes in other aspects of cellular function. In this review, emphasis is placed on novel hypotheses and various findings that have not yet been dealt with in a critical review. Emerging studies indicate their role in various cellular processes other than host defense, virulence, and even controlling the rate of evolution of the organism. We also discuss how R-M systems could have successfully evolved and be involved in additional cellular portfolios, thereby increasing the relative fitness of their hosts in the population.

SUBMITTER: Vasu K

PROVIDER: S-EPMC3591985 | biostudies-literature | 2013 Mar

REPOSITORIES: biostudies-literature

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Diverse functions of restriction-modification systems in addition to cellular defense.

Vasu Kommireddy K Nagaraja Valakunja V

Microbiology and molecular biology reviews : MMBR 20130301 1

Restriction-modification (R-M) systems are ubiquitous and are often considered primitive immune systems in bacteria. Their diversity and prevalence across the prokaryotic kingdom are an indication of their success as a defense mechanism against invading genomes. However, their cellular defense function does not adequately explain the basis for their immaculate specificity in sequence recognition and nonuniform distribution, ranging from none to too many, in diverse species. The present review de ...[more]

PMID: 23471617

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Diverse functions of restriction-modification systems in addition to cellular defense.

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Diverse functions of restriction-modification systems in addition to cellular defense.

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