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Shifts in growth strategies reflect tradeoffs in cellular economics.

ABSTRACT: The growth rate-dependent regulation of cell size, ribosomal content, and metabolic efficiency follows a common pattern in unicellular organisms: with increasing growth rates, cell size and ribosomal content increase and a shift to energetically inefficient metabolism takes place. The latter two phenomena are also observed in fast growing tumour cells and cell lines. These patterns suggest a fundamental principle of design. In biology such designs can often be understood as the result of the optimization of fitness. Here we show that in basic models of self-replicating systems these patterns are the consequence of maximizing the growth rate. Whereas most models of cellular growth consider a part of physiology, for instance only metabolism, the approach presented here integrates several subsystems to a complete self-replicating system. Such models can yield fundamentally different optimal strategies. In particular, it is shown how the shift in metabolic efficiency originates from a tradeoff between investments in enzyme synthesis and metabolic yields for alternative catabolic pathways. The models elucidate how the optimization of growth by natural selection shapes growth strategies.

SUBMITTER: Molenaar D

PROVIDER: S-EPMC2795476 | biostudies-literature | 2009

REPOSITORIES: biostudies-literature

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Shifts in growth strategies reflect tradeoffs in cellular economics.

Molenaar Douwe D van Berlo Rogier R de Ridder Dick D Teusink Bas B

Molecular systems biology 20091103

The growth rate-dependent regulation of cell size, ribosomal content, and metabolic efficiency follows a common pattern in unicellular organisms: with increasing growth rates, cell size and ribosomal content increase and a shift to energetically inefficient metabolism takes place. The latter two phenomena are also observed in fast growing tumour cells and cell lines. These patterns suggest a fundamental principle of design. In biology such designs can often be understood as the result of the opt ...[more]

PMID: 19888218

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Shifts in growth strategies reflect tradeoffs in cellular economics.

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Shifts in growth strategies reflect tradeoffs in cellular economics.

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