![]() |
|
||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
![]()
![]()
![]()
Key reference
DOI no: 10.1016/S0022-2836(02)00387-X J Mol Biol 320:303-309 (2002) PubMed id: 12079387 ![]()
A novel combination of two classic catalytic schemes. A.Shaw, R.Bott, C.Vonrhein, G.Bricogne, S.Power, A.G.Day. ![]()
ABSTRACT ![]()
![]()
The crystal structure of an alkaline Bacillus cellulase catalytic core, from glucoside hydrolase family 5, reveals a novel combination of the catalytic machinery of two classic textbook enzymes. The enzyme has the expected two glutamate residues in close proximity to one another in the active-site that are typical of retaining cellulases. However, the proton donor, glutamate 139 is also unexpectedly a member of a serine-histidine-glutamate catalytic triad, forming a novel combination of catalytic machineries. Structure and sequence analysis of glucoside hydrolase family 5 reveal that the triad is highly conserved, but with variations at the equivalent of the serine position. We speculate that the purpose of this novel catalytic triad is to control the protonation of the acid/base glutamate, facilitating the first step of the catalytic reaction, protonation of the substrate, by the proton donor glutamate. If correct, this will be a novel use for a catalytic triad.
![]()
![]()
![]()
Selected figure(s) ![]()
![]()
The above figures are reprinted by permission from Elsevier: J Mol Biol (2002, 320, 303-309) copyright 2002. ![]()
Literature references that cite this PDB file's key reference
PubMed id Reference
![]()
17905739 Y.Kitago, S.Karita, N.Watanabe, M.Kamiya, T.Aizawa, K.Sakka, and I.Tanaka (2007).
Crystal structure of Cel44A, a glycoside hydrolase family 44 endoglucanase from Clostridium thermocellum.J Biol Chem, 282, 35703-35711.
PDB codes: 2e0p 2e4t 2eex 2ej1 2eo7 2eqd
![]()
16193230 E.A.Zvereva, T.V.Fedorova, V.V.Kevbrin, T.N.Zhilina, and M.L.Rabinovich (2006).
Cellulase activity of a haloalkaliphilic anaerobic bacterium, strain Z-7026.Extremophiles, 10, 53-60.
![]()
16320365 S.W.Hinz, C.H.Doeswijk-Voragen, R.Schipperus, L.A.van den Broek, J.P.Vincken, and A.G.Voragen (2006).
Increasing the transglycosylation activity of alpha-galactosidase from Bifidobacterium adolescentis DSM 20083 by site-directed mutagenesis.Biotechnol Bioeng, 93, 122-131.
![]()
12454011 A.Haouz, V.Vanheusden, H.Munier-Lehmann, M.Froeyen, P.Herdewijn, S.Van Calenbergh, and M.Delarue (2003).
Enzymatic and structural analysis of inhibitors designed against Mycobacterium tuberculosis thymidylate kinase. New insights into the phosphoryl transfer mechanism.J Biol Chem, 278, 4963-4971.
PDB codes: 1mrn 1mrs
![]()
12823562 M.M.Sánchez, F.I.Pastor, and P.Diaz (2003).
Exo-mode of action of cellobiohydrolase Cel48C from Paenibacillus sp. BP-23. A unique type of cellulase among Bacillales.Eur J Biochem, 270, 2913-2919. The most recent references are shown first. Citation data come partly from CiteXplore and partly from an automated harvesting procedure. Note that this is likely to be only a partial list as not all journals are covered by either method. However, we are continually building up the citation data so more and more references will be included with time. Where a reference describes a PDB structure, the PDB codes are shown on the right.