3HZ2
Crystal structure of a betagamma-crystallin from an Archaea
Summary for 3HZ2
Entry DOI | 10.2210/pdb3hz2/pdb |
Related | 2BV2 2K1W 3HZB |
Descriptor | Beta/gama crystallin family protein, CALCIUM ION (3 entities in total) |
Functional Keywords | calcium-bound betagamma-crystallin, metal binding protein |
Biological source | Methanosarcina acetivorans |
Total number of polymer chains | 4 |
Total formula weight | 37332.53 |
Authors | Aravind, P.,Sankaranarayanan, R. (deposition date: 2009-06-23, release date: 2009-12-01, Last modification date: 2023-11-01) |
Primary citation | Aravind, P.,Mishra, A.,Suman, S.K.,Jobby, M.K.,Sankaranarayanan, R.,Sharma, Y. The betagamma-crystallin superfamily contains a universal motif for binding calcium Biochemistry, 48:12180-12190, 2009 Cited by PubMed Abstract: The betagamma-crystallin superfamily consists of evolutionarily related proteins with domain topology similar to lens beta- and gamma-crystallins, formed from duplicated Greek key motifs. Ca(2+) binding was found in a few betagamma-crystallin members earlier, although its prevalence and diversity as inherent molecular properties among members of the superfamily are not well studied. To increase our understanding of Ca(2+) binding in various betagamma-crystallins, we undertook comprehensive structural and Ca(2+)-binding studies of seven members of the superfamily from bacteria, archaea, and vertebrates, including determination of high-resolution crystal structures of three proteins. Our structural observations show that the determinants of Ca(2+) coordination remain conserved in the form of an N/D-N/D-#-I-S/T-S motif in all domains. However, binding of Ca(2+) elicits varied physicochemical responses, ranging from passive sequestration to active stabilization. The motif in this superfamily is modified in some members like lens crystallins where Ca(2+)-binding abilities are partly or completely compromised. We show that reduction or loss of Ca(2+) binding in members of the superfamily, particularly in vertebrates, is due to the selective presence of unfavorable amino acids (largely Arg) at key Ca(2+)-ligation positions and that engineering of the canonical Ca(2+)-binding residues can confer binding activity on an otherwise inactive domain. Through this work, we demonstrate that betagamma-crystallins with the N/D-N/D-#-I-S/T-S motif form an extensive set of Ca(2+)-binding proteins prevalent in all of the three kingdoms of life. PubMed: 19921810DOI: 10.1021/bi9017076 PDB entries with the same primary citation |
Experimental method | X-RAY DIFFRACTION (1.86 Å) |
Structure validation
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