2B5D

Crystal structure of the novel alpha-amylase AmyC from Thermotoga maritima

Summary for 2B5D

• Entry DOI: 10.2210/pdb2b5d/pdb
• Related: 1UFA
• Descriptor: alpha-Amylase (2 entities in total)
• Functional Keywords: (beta/alpha)7 barrel, hydrolase
• Biological source: Thermotoga maritima
• Total number of polymer chains: 1
• Total formula weight: 62942.57

Authors

Dickmanns, A.,Ballschmiter, M.,Liebl, W.,Ficner, R. (deposition date: 2005-09-28, release date: 2006-03-07, Last modification date: 2024-03-13)

Primary citation

Dickmanns, A.,Ballschmiter, M.,Liebl, W.,Ficner, R.
Structure of the novel alpha-amylase AmyC from Thermotoga maritima.
Acta Crystallogr.,Sect.D, 62:262-270, 2006

PubMed Abstract: alpha-Amylases are essential enzymes in alpha-glucan metabolism and catalyse the hydrolysis of long sugar polymers such as amylose and starch. The crystal structure of a previously unidentified amylase (AmyC) from the hyperthermophilic organism Thermotoga maritima was determined at 2.2 Angstroms resolution by means of MAD. AmyC lacks sequence similarity to canonical alpha-amylases, which belong to glycosyl hydrolase families 13, 70 and 77, but exhibits significant similarity to a group of as yet uncharacterized proteins in COG1543 and is related to glycerol hydrolase family 57 (GH-57). AmyC reveals features that are characteristic of alpha-amylases, such as a distorted TIM-barrel structure formed by seven beta-strands and alpha-helices (domain A), and two additional but less well conserved domains. The latter are domain B, which contains three helices inserted in the TIM-barrel after beta-sheet 2, and domain C, a five-helix region at the C-terminus. Interestingly, despite moderate sequence homology, structure comparison revealed significant similarities to a member of GH-57 with known three-dimensional structure, Thermococcus litoralis 4-glucanotransferase, and an even higher similarity to a structure of an enzyme of unknown function from Thermus thermophilus.

PubMed: 16510973
DOI: 10.1107/S0907444905041363

Experimental method

X-RAY DIFFRACTION (2.2 Å)