| isolation and characterization of psychrophiles producing cold-active beta-galactosidase. | the present study was conducted to screen for psychrophilic micro-organisms that are able to hydrolyse lactose at low temperature, and to examine the cold-active beta-galactosidase produced by the isolated psychrophilic micro-organisms. | 2003 | 12859659 |
| polyphasic taxonomic study of strain ccm 2783 resulting in the description of arthrobacter stackebrandtii sp. nov. | strain ccm 2783, previously classified as representing arthrobacter aurescens, was subjected to a polyphasic taxonomic study. 16s rrna gene sequence analysis and chemotaxonomic characteristics such as peptidoglycan type a3alpha lys-ala(2), major menaquinone mk-9(h(2)) and fatty acid composition confirmed assignment of the strain to the genus arthrobacter. the results of phylogenetic analysis, dna-dna relatedness experiments and physiological and chemotaxonomic characteristics indicate that ccm 2 ... | 2005 | 15774666 |
| production of amylase by arthrobacter psychrolactophilus. | arthrobacter psychrolactophilus atcc 700733 grew with a doubling time of 1.5-2.3 h (22 degrees c) and produced up to 0.2 units/ml (soluble starch assay) of extracellular amylase in tryptic soy broth without dextrose (tsbwd) containing 0.5% or 1.0% (w/v) soluble starch or maltose as the fermentable substrate. time-course experiments in media containing soluble starch as substrate showed that amylolytic activity appeared in cultures at 24 h (after exponential growth had ceased), reached peak level ... | 2005 | 15931519 |
| characteristics of the amylase of arthrobacter psychrolactophilus. | properties of the extracellular amylase produced by the psychrotrophic bacterium, arthrobacter psychrolactophilus, were determined for crude preparations and purified enzyme. the hydrolysis of soluble starch by concentrated crude preparations was found to be a nonlinear function of time at 30 and 40 degrees c. concentrates of supernatant fractions incubated without substrate exhibited poor stability at 30, 40, or 50 degrees c, with 87% inactivation after 21 h at 30 degrees c, 45% inactivation af ... | 2005 | 16133101 |
| purification and molecular characterization of cold-active beta-galactosidase from arthrobacter psychrolactophilus strain f2. | in this study, we purified and molecularly characterized a cold-active beta-galactosidase from arthrobacter psychrolactophilus strain f2. the purified beta-galactosidase from strain f2 exhibited high activity at 0 degrees c, and its optimum temperature and ph were 10 degrees c and 8.0, respectively. it was possible to inactivate the beta-galactosidase rapidly at 45 degrees c in 5 min. the enzyme was able to hydrolyze lactose as a substrate, as well as o-nitrophenyl-beta-d-galactopyranoside (onpg ... | 2006 | 16607530 |
| overexpression and functional analysis of cold-active beta-galactosidase from arthrobacter psychrolactophilus strain f2. | cold-active beta-galactosidase from arthrobacter psychrolactophilus strain f2 was overexpressed in escherichia coli using the cold expression system and the recombinant enzyme, rbglap, was characterized. the purified rbglap exhibited similar enzymatic properties to the native enzyme, e.g., (i) it had high activity at 0 degrees c, (ii) its optimum temperature and ph were 10 degrees c and 8.0, respectively, and (iii) it was possible to rapidly inactivate the rbglap at 50 degrees c in 5 min. moreov ... | 2007 | 17459724 |
| selection of a cold-adapted bacterium for bioremediation of wastewater at low temperatures. | amongst more than 1000 isolates collected in various cold environments, the strain arthrobacter psychrolactophilus sp 31.3 has been selected for its ability to grow and to produce exoenzymes at low temperatures, its inability to grow at 37 degrees c, its non-halophilic character and its growth versatility on various media. this non-pathogenic strain displays a strong resistance to desiccation and storage at room temperature and is suitable for the production of freeze-dried bacterial starters. w ... | 2009 | 19578929 |
| arthrobacter psychrochitiniphilus sp. nov., a psychrotrophic bacterium isolated from antarctica. | a psychrotrophic arthrobacter strain, gp3(t), was isolated from adélie penguin guano from antarctica and characterized. the 16s rrna gene sequence of the novel strain showed the highest similarity (97.8 %) with that of arthrobacter psychrolactophilus b7(t). the novel strain showed a morphological change from rod to coccus. the growth temperature range of strain gp3(t) was 0-25 degrees c, with optimal growth at 20 degrees c. the strain grew over a salinity range of between 0 and 3 % (w/v) nacl an ... | 2009 | 19625417 |
| arthrobacter alpinus sp. nov., a psychrophilic bacterium isolated from alpine soil. | an aerobic, gram-reaction-positive, non-motile, psychrophilic bacterium, designated strain s6-3(t), was isolated from alpine soil. cells exhibited a rod-coccus growth cycle and produced a yellow pigment. growth occurred at 1-25 degrees c. phylogenetic analysis based on 16s rrna gene sequences showed that strain s6-3(t) was related to members of the genus arthrobacter, sharing highest sequence similarities with the type strains of arthrobacter psychrolactophilus (97.9 %) and arthrobacter stackebr ... | 2010 | 19880631 |
| biochemical and phylogenetic analyses of psychrophilic isolates belonging to the arthrobacter subgroup and description of arthrobacter psychrolactophilus, sp. nov. | during our work on psychrophilic microorganisms we obtained a large collection of new isolates. in order to identify six of these, we examined their growth properties, cell wall compositions, and their 16s rrna gene sequences. the results showed that all of the isolates are gram-positive, aerobic, contain lysine in their cell walls, and belong to the high mol% g+c arthrobacter subgroup. phylogenetic analysis of the 16s rrna genes grouped five isolates obtained from a small geographical region in ... | 1999 | 10369891 |