HMM Summary Page: TIGR01370

Functionextracellular protein
Trusted Cutoff181.25
Domain Trusted Cutoff181.25
Noise Cutoff33.65
Domain Noise Cutoff33.65
Isology Typehypoth_equivalog
HMM Length315
Mainrole CategoryProtein synthesis
Subrole CategorytRNA aminoacylation
Gene Ontology TermGO:0004817: cysteine-tRNA ligase activity molecular_function
GO:0006423: cysteinyl-tRNA aminoacylation biological_process
AuthorHaft DH
Entry DateOct 31 2001 9:35AM
Last ModifiedFeb 6 2012 10:44AM
CommentOriginal assignment of this protein family as cysteinyl-tRNA synthetase is controversial, supported by PMID:11333988 but challenged by PMID:14679218 and by subsequent discovery of the actual mechanism for synthesizing Cys-tRNA in species where a direct Cys--tRNA ligase was not found. Lingering legacy annotations of members of this family probably should be removed. Evidence against the role includes a signal peptide. This family as been renamed "extracellular protein" to facilitate correction. Members of this family occur in Deinococcus radiodurans (bacterial) and Methanococcus jannaschii (archaeal). A number of homologous but more distantly related proteins are annotated as alpha-1,4 polygalactosaminidases. The function remains unknown.
ReferencesRN [1] RM PMID:11790254 RT Quoderat demonstrandum? The mystery of experimental validation of apparently erroneous computational analyses of protein sequences. RA Iyer LM, Aravind L, Bork P, Hofmann K, Mushegian AR, Zhulin IB, Koonin EV RL Genome Biol. 2001;2(12):RESEARCH0051. RN [2] RM 14679218 RT Cysteinyl-tRNA(Cys) formation in Methanocaldococcus jannaschii: the mechanism is still unknown. RA Ruan B, Nakano H, Tanaka M, Mills JA, DeVito JA, Min B, Low KB, Battista JR, Soll D. RL J Bacteriol. 2004 Jan;186(1):8-14. RN [3] RM 11333988 RT An aminoacyl tRNA synthetase whose sequence fits into neither of the two known classes. RA Fabrega C, Farrow MA, Mukhopadhyay B, de Crecy-Lagard V, Ortiz AR, Schimmel P. RL Nature 2001 May 3;411(6833):110-4