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The significance of nitrogen cost minimization in proteomes of marine microorganisms.

ABSTRACT: Marine microorganisms thrive under low levels of nitrogen (N). N cost minimization is a major selective pressure imprinted on open-ocean microorganism genomes. Here we show that amino-acid sequences from the open ocean are reduced in N, but increased in average mass compared with coastal-ocean microorganisms. Nutrient limitation exerts significant pressure on organisms supporting the trade-off between N cost minimization and increased average mass of amino acids that is a function of increased A+T codon usage. N cost minimization, especially of highly expressed proteins, reduces the total cellular N budget by 2.7-10%; this minimization in combination with reduction in genome size and cell size is an evolutionary adaptation to nutrient limitation. The biogeochemical and evolutionary precedent for these findings suggests that N limitation is a stronger selective force in the ocean than biosynthetic costs and is an important evolutionary strategy in resource-limited ecosystems.

SUBMITTER: Grzymski JJ

PROVIDER: S-EPMC3246230 | biostudies-literature | 2012 Jan

REPOSITORIES: biostudies-literature

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The significance of nitrogen cost minimization in proteomes of marine microorganisms.

Grzymski Joseph J JJ Dussaq Alex M AM

The ISME journal 20110623 1

Marine microorganisms thrive under low levels of nitrogen (N). N cost minimization is a major selective pressure imprinted on open-ocean microorganism genomes. Here we show that amino-acid sequences from the open ocean are reduced in N, but increased in average mass compared with coastal-ocean microorganisms. Nutrient limitation exerts significant pressure on organisms supporting the trade-off between N cost minimization and increased average mass of amino acids that is a function of increased A ...[more]

PMID: 21697958

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Dataset Information

The significance of nitrogen cost minimization in proteomes of marine microorganisms.

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The significance of nitrogen cost minimization in proteomes of marine microorganisms.

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