Enzyme Arthrobacter

The enzymes from Arthrobacter, Bacillus stearothermophilus NCIB 8224 and NS 1122A, and Pseudomonas sp. NS 671 have been cloned and expressed in E. coli. The enzymes from Bacillus and Pseudomonas share approximately 38% sequence identity with the Arthrobacter enzyme whereas the 20 amino acids known from the N-termini of the enzymes from Alcaligenes and Pseudomonas putida IFO 12996 are... 

As expected, Frc-S-ME was hardly hydrolyzed by several P-fructofuranosidases [8]. The inhibition experiment (Table 24.4) revealed that 5-fructoside inhibited the enzymes competitively, except the Arthrobacter enzyme, which did not synthesize... 

The actions of the two chondroitinases AC have been compared via steady-state kinetics carried out at pH 6.0. The Arthrobacter enzyme was susceptible to salt activation/regression and bivalent metal ions such as Ca +, Co +, Mg +, and Ba + were more effective for activation than virulent ions such as Na+ and K+. Various kinetic parameters of the actions of the enzymes was determined and thermodynamic parameters were calculated. The results obtained suggested that the driving force of enzyme-substrate complex formation could be attributed to ionic interaction for Arthrobacter chondroitinase AC and to hydrophobic bonding for Flavobacterium chondroitinase AC. 

Detailed kinetic analysis of the catalytic mechanism of the Arthrobacter enzyme by Rangarajan and Hartley [58] also supported the hydride shift mechanism. However, these workers imply different reaction pathways for the Mg and the Co + enzymes. The rate-limiting step was inferred to be the isomerisation and not the ring opening, in contrast to the results of Zeikus and co-workers. Reports from Withlow and co-workers [59] as well as Collyer and his group [60] provided further support for the hydride shift mechanism. 

Recently, recombinant biocatalysts obtained using Escherichia coli cells were designed for this process. The overexpression of all enzymes required for the process, namely, hydantoinase, carbamoylase, and hydantoin racemase from Arthrobacter sp. DSM 9771 was achieved. These cells were used for production of a-amino acids at the concentration of above 50 g 1 dry cell weight [37]. This is an excellent example presenting the power of biocatalysis with respect to classical catalysis, since a simultaneous use of three different biocatalysts originated from one microorganism can be easily achieved. 

The metabolism of 2-methylquinoline in Arthrobacter sp. strain Rii 61a is comparable, with introduction of oxygen at C4 (Hund et al. 1990). The enzymes (oxidoreductases) that introduce oxygen into the azaarene rings in Rhodococcus sp. strain Bl, Arthrobacter sp. strain Rii61a, and Pseudomonas putida strain 86 are virtually identical and, like those already noted have molecular masses of 300-320 kDa and contain Mo, Fe, FAD, and acid-labile sulfur (De Beyer and Lingens... 

De Beyer A, F Lingens (1993) Microbial metabolism of quinoline and related compounds XVI. Quinaldine oxidoreductase from Arthrobacter spec. Rii 61a a molybdenum-containing enzyme catalysing the hydroxylation at C-4 of the heterocycle. Biol Chem Hoppe-Seyler 374 101-120. 

Schenk S, A Hoelz, B Krauss, K Decker (1998) Gene structures and properties of enzymes of the plasmid-encoded nicotine catabolism of Arthrobacter nicotinovorans. J Mol Biol 284 1323-1339. 

Chen, Y.-R., Huang, H.-H., Cheng, Y.-F. et al. (2006) Expression of a cholesterol oxidase gene from Arthrobacter simplex in Escherichia coli and Pichia pastoris. Enzyme and Microbial Technology, 39, 854-860. 

Arthrobacter sp. Ru61a Gram (+) [327,350] Susanne Fetzner Quinaldine 4-OR BDN of 2-MeQN through the anthranilic acid pathway. Activity is about 70 times improved by purification from the crude extract. Enzyme activity for QN is three times higher than for quinaldine (2Me-QN). Enzyme selective to most of heterocyclic N-compounds. Attack at the 4th (para)-position. 

The decrease of peak numbers was observed, when the spectra of the same amounts of fresh (12 weeks old) and aged (9 months old) mortars were compared. This decrease might be caused by activity of ubiquitous microorganisms that live on the mortar surfaces in biofilms. Especially in mild climate conditions, algae and cyanobacteria [35] can appear here moulds (Aspergillus, Penicillium, Fusarium, Mucor) [36] and bacteria (Arthrobacter Bacillus, Micrococcus, Staphylococcus) [37,38] have been discovered as well. The microorganisms secrete various hydrolytic enzymes that can decompose the organic additives, namely proteins, and make their sample identification less sensitive... 

Borodina E, Kelly DP, Schumann P, et al. 2002. Enzymes of dimethylsulfone metabolism and the phylogenetic characterization of the facultative methylotrophs Arthrobacter sulfonivorans sp. nov., Arthrobacter methylotrophus sp. nov., and Hyphomicrobium sulfonivorans sp. nov. Arch Microbiol 177 173-83. 

Many microorganisms produce enzymes that lyse the cell wall of yeast. The most extensive work has been done with the lytic system from Arthrobacter sp., Cytophaga sp., Oerskovia, Bacillus circulans, Rhizopus, Tri-choderma, Penicillium, Pellicularia sp., Rhizoctonia, and Streptomyces sp. (3-9). 

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