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. 2001 Feb;2(1):14–18. doi: 10.1002/cfg.66

Conserved ‘Hypothetical’ Proteins: New Hints and New Puzzles

Michael Y Galperin 1,✉
PMCID: PMC2447192  PMID: 18628897

Abstract

Conserved hypothetical proteins, i.e. conserved proteins whose functions are still unknown, pose a challenge not just to functional genomics but also to general biology. For many conserved proteins, computational analysis provides only a general prediction of biochemical function; their exact biological functions have to be established through direct experimentation. In the few cases when this has been accomplished, the results were remarkable, revealing the deoxyxylulose pathway and a new essential enzyme, the ITP pyrophosphatase. Comparative genome analysis is also instrumental in illuminating unsolved problems in biology, e.g. the mechanism of FtsZ-independent cell division in Chlamydia, Ureaplasma and Aeropyrum or the role of uncharacterized conserved domains in signal transduction.

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Selected References

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