Thermophilic hydrolase

Within the cellulosome complex, type I dockerin domain is responsible for incorporating its associated glycosyl hydrolase in the bacterial cellulosome via interaction with a reception domain, the cohesin domain. The three-dimensional solution structure of the 69-residue dockerin domain from the thermophilic Clostridium thermocellum (Topt = 55-65 °C) was solved by NMR and was found to consist of two Ca " -binding loop-helix motifs connected by a linker. Each Ca " -binding subdomain is stabilized by a cluster of buried hydrophobic sidechains. Recently, the NMR sequence-specific resonance assignment of type II cohesin module from C. thermocellum has been published. ... 

Walls, L.H. 1987. Isolation and purification of a diisopropyl phosphorofluoridate hydrolase from thermophilic bacteria. CRDEC-CR-87072. 

Blumer-Schuette SE, Lewis DL, KeUy RM. (2010). Phylogenetic, microbiological and glycoside hydrolase diversities within the extremely thermophilic, plant biomass-degrading genus Caldicellulosiruptor. Appl Environ Microbiol, 76, 8084—8092. 

Aeromonas proteolytica aminopeptidase [a-Aminoacylpeptide hydrolase (Aeromonas proteolytica)] (3.4.11.10) is produced. [A zinc enzyme. Acts most rapidily on L-leucylpeptides, amide and B-naphthylamide. Does not cleave Glu-and Asp-bonds. Similar aminopeptidases were isolated from E, coli and Staphylococcus thermophilus. ] Thermophilic aminopeptidase [a-Aminoacylpeptide hydrolase] (3.4.11.12) is produced. [Metalloen-zymes of high temperature stability and of broad specificity, releasing all N-terminal amino acids, including arginine and lysine. Isolated from Bacillus St ear othermophilus, Talaromyces duponti, Mucor. ]... 

The lipase from the thermophilic filamentous fungus T. lanuginosus (formerly Humicola lanuginosus) consists of 269 amino acids and has a molecular mass of 31.7 kDa [30]. It contains a a//i-hydrolase tertiary fold consisting of a nine-... 

The production of thermostable enzymes, catalyzing reactions at high temperatures, is one of the most attractive features of thermophilic microorganisms. In order to select producers of thermostable hydrolases, different aerobic thermophilic bacterial strains were Isolated from water, soil and organic material samples collected from Bulgarian hot springs environment. Some of the properties of the Isolated strains were a subject of our previous work [1]. The aim of the present paper was to characterize and identify the strain producing thermostable pullulanase as well as to establish the optimum conditions for enzyme production and to study some of the enzyme s properties. 

This review on enzymes from extreme thermophiles (optimum growth temperature > 65 °C) concentrates on their characteristics, especially thermostabilities, and their commercial applicability. The enzymes are considered in general terms first, with comments on denaturation, stabilization and industrial processes. Discussion of the enzymes subsequently proceeds in order of their E.C. classification oxidoreductases, transferases, hydrolases, lyases, isomerases and ligases. The ramifications of cloned enzymes from extreme thermophiles are also discussed. 

Few other peptide hydrolases from thermophiles have been purified. Cho et al. [299] in studying the aminoacylase from the moderate thermophile Bacillus thermoglucosidus found it to have hydrolytic activity against several dipeptides and mention a dipeptidase with high activity against L-valyl-L-alanine, but no characterization was undertaken. Subsequent screening of Bacillus species for... 

Amylases classified in family 13 glycoside hydrolases have been described from the archaea to the bacteria domains. The genus Bacillus includes a set of species able to produce starch-d rading enzymes and has biotechnological potential as a source of these enzymes especially the a-amylases, which are the most fi equent starch-degrading enzymes described for bacteria. In addition. Bacillus a-amylases present activity and are stable in temperatures over 50-60 °C, therefore are very attractive for industrial applications. B. subtilis, Bacillus stearothermophilus. Bacillus lichenifortnis, and Bacillus atnyloliquefaciens have been widely used for commercial production of amylases and for the production of starch derivates. The a-amylases produced by other bacteria and also archaea have to compete with the Bacillus enzymes that already present excellent thermophilic properties and high conversion rates (Prakash and Jaiswal 2010). 

Schwarz WH (2004) Cellulose - Struktur ohne Ende. Naturwiss Rundschau 8 443-445 Schwarz WH, Bronnenmeier K, Landmann B, Warmer G, Staudenbauer WL, Kurose N, Takayama T (1995) Molecular characterization of four strains of the cellulolytic thermophile Clostridium stercorarium. Biosci Biotechnol Biochem 59 1661-1665 Schwarz WH, Zverlov VV, Bahl H (2004) Extracellular glycosyl hydrolases fiom Clostridia. Adv Appl Microbiol 56 215-261... 

Cellulosomes are extracellular multiprotein complexes first identified in early 1980s, on the thermophilic anaerobic bacteria Clostridium thermocellum. Since then, several other cellulolytic bacteria and fungi have been reported to produce cellulosomes [38]. In 1999, a cehulosome holding a glycosyl hydrolase in the scaffoldin subunity was described, and later on Xu and colleagues (2004) reported another scaffoldin protein from a Bacteroides cellulosolvens cehulosome that includes a cehulase [38-43]. 

Boraston and coworkers identified a family 6 CBM present as a triplet in C. stercorarium. The multiple modules act cooperatively in the binding process. It has been suggested that the duplication or triplication of CBMs may, evolutionary, balance the loss of binding affinity of thermophilic glycosyl hydrolases at higher temperatures [62]. 

Lieshout, J. V., Faijes, M., Nieto, J., Van Der Oost, J. Planas, A. (2004). Hydrolase and glycosynthase activity of endo-l,3-P glucanase from the thermophile Pyrococcus furlosus. Archaea, 1, 285-292. 

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