Pseudomonas strains screening

Specific information about the optimum conditions for the synthesis and the activity of the enzyme has been reported for Pseudomonas fluorescens screening of various micro-organisms resulted in the selection of a P. fluorescens strain with an initial rate of conversion of 3 g P h 1 in an imoptimised state. The following conclusions could be made concerning the production of L-phenylalanine by P. fluorescens ... 

By screening 53 Rhodococcus and Pseudomonas strains, an NHase-amidase biocatalyst system was identified for the production of the 2,2-dimethylcyclopropane carboxylic acid precursor of the dehydropeptidase inhibitor Cilastatin, which is used to prolong the antibacterial effect of Imipenem. A systematic study of the most selective of these strains, Rhodococcus erythropolis ATCC25 544, revealed that maximal product formation occurs at pH 8.0 but that ee decreased above pH 7.0. In addition, significant enantioselectivity decreases were observed above 20 °C. A survey of organic solvent effects identified methanol (10% v/v) as the... 

Previously, we have screened the literature for relevant biochemical studies on enzyme systems that oxidize medium chain-length alkanes (1). The Pseudomonas strains mentioned in this paper have been studied in varying detail with respect to the enzymology of medium chain-length alkane metabolism. The alkane hydroxylase systems in these strains show a number of differences, such as the apparent absence of rubredoxin in P. aeruginosa 196 Aa (12). On the whole, however, they resemble each other, and the system of P. oleovorans GPol. As an example, we found that the described substrate range of the paraffin hydroxylase of... 

It is known that NHase used in industry has a lower optimum temperature," therefore many reports have been concerned with screening for thermostable NHase. Miyanaga et al. has succeeded to analyze the X-ray structure of such a thermostable NHase from Pseudomonas thermophila. Bacillus sp. BR449 producing NHase with optimum temperature of 55°C has been isolated. Similarly, Bacillus sp. RAPc8 has a growth optimum at 65°C. Takashima et al. has isolated Bacillus smithii strain SC-J05-1, with optimum temperature at 40°C, and whose NHase has an optimum temperature and pH of 50°C and 10, respectively. Its crystal structure has also been elucidated. Bacillus pallidus strain Dac521 has... 

A BDS patent [106] was awarded for the use of biocatalysts belonging to the group of Pseudomonas, Flavobacterium, Enterobacter, Aeromonas, Bacillus, or Corynebac-terium. One of the strains P. putida was further developed by mutation of the parent strain to obtain organic solvent-resistant mutants [107], The mutated strains were screened by selective cultivation in the presence of 0.1% to 10% by volume (v/v) of concentrations of a toxic organic solvent. The specific mutated strains obtained were P. putida No. 69-1 (PERM BP-4519), P. putida No. 69-2 (PERM BP-4520), and P. putida No. 69-3 (PERM BP-4521). 

Two strains were isolated and purified, Pseudomonas sp. CDT-4, and Nocardia aster-oides, CDT-4b (ATCC 202160 and 202161, respectively). The microbes were passed through a multiple screen, first to allow growth on dibenzothiophene (DBT) as a sole source of sulfur, and then on fossil fuels, to identify organisms capable of desulfurization without metabolizing the DBT phenyl ring structures. N. asteroides sp. CDT-4b was found to metabolize DBT. The Pseudomonas species was found to utilize trace levels of sulfate from media and was found to be incapable of growth on DBT as a sole source of sulfur. However, the co-culture could remove more than 20% sulfur, with supplementation of a second sulfur-free carbon source. 

A microbial resolution of racemic 2-methylbutanoic acid was performed with a novel Pseudomonas sp. strain isolated from soil [40]. The strain was selected by screening on a medium containing racemic 2-methylbutanoic acid as the sole carbon source. The strain preferentially catabolised the fruity (S)-2-methylbuta-noic acid, thereby yielding optically pure (J )-2-methylbutanoic acid which has a distinct odour described as being cheesy, sweaty and sharp. 

In an alternate process, enantioselective microbial reduction of 6-oxobus-pirone (19, Fig. 18.6) to either (R)- and (.S )-6-hydroxybuspirone was described. About 150 microorganisms were screened for the enantioselective reduction of 19. Rhizopus stolonifer SC 13898, Rhizopus stolonifer SC 16199, Neuros-pora crassa SC 13816, Mucor racemosus SC 16198, and Pseudomonas putida SC 13817 gave >50% reaction yields and >95% ee s of (,S )-6-hydroxybuspi-rone. The yeast strains Hansenula polymorpha SC 13845 and Candida maltosa SC 16112 gave (R)-6-hydroxybuspirone in >60% reaction yield and >97% ee (Patel et aL, 2005). 

In vitro screening of bacteria by promazine (Table 5) indicate that strains of Bacillus Staphylococcus aureus and Vibrio cholerae were most sensitive to the compound, while strains of Proteus, Klebsiella, Pasteurella, and Pseudomonas were resistant. The other bacteria were moderately sensitive to the drug. 

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