Control of a pyrimidine ribonucleotide salvage pathway in Pseudomonas oleovorans.

The control of a pyrimidine ribonucleotide salvage pathway in the bacterium Pseudomonas oleovorans ATCC 8062 was studied. This bacterium is important for its ability to synthesize polyesters as well as for its increasing clinical significance in humans. The pyrimidine salvage pathway enzymes pyrimidine nucleotide N-ribosidase and cytosine deaminase were investigated in P.

Effect of pH on xylitol production by Candida species from a prairie cordgrass hydrolysate.

Using hydrolysates of the North American prairie grass prairie cordgrass buffered at pH 4.5, 5.0, 5.

Control of pyrimidine nucleotide formation in Pseudomonas aurantiaca.

The control of pyrimidine nucleotide formation in the bacterium Pseudomonas aurantiaca ATCC 33663 by pyrimidines was studied. The activities of the pyrimidine biosynthetic pathway enzymes were investigated in P. aurantiaca ATCC 33663 cells and from cells of an auxotroph lacking orotate phosphoribosyltransferase activity under selected culture conditions.

The pyrimidine biosynthetic pathway and its regulation in Pseudomonas jessenii.

The control of the pyrimidine biosynthetic pathway by pyrimidine bases was examined in Pseudomonas jessenii ATCC 700870. The pyrimidine biosynthetic enzymes aspartate transcarbamoylase, dihydroorotase, dihydroorotate dehydrogenase, orotate phosphoribosyltransferase, and orotidine 5'-monophosphate (OMP) decarboxylase activities were found to be higher in the succinate-grown ATCC 700870 cells than the glucose-grown cells. All the enzyme activities were depressed in uracil-supplemented ATCC 700870 glucose-grown cells relative to the unsupplemented cells which was indicative of possible repression of enzyme synthesis by uracil.

Effect of yeast extract addition to a mineral salts medium containing hydrolyzed plant xylan on fungal pullulan production.

The ability of the fungus Aureobasidium pullulans ATCC 42023 to produce pullulan from yeast extract-supplemented xylan hydrolysates of the prairie grass prairie cordgrass was examined relative to polysaccharide and cell biomass production, yield, and pullulan content of the polysaccharide. A pullulan concentration of 11.2 g L-1 and yield of 0.

Pyrimidine nucleotide synthesis in the emerging pathogen Pseudomonas monteilii.

Regulation of pyrimidine biosynthesis by pyrimidines in the emerging, opportunistic human pathogen Pseudomonas monteilii ATCC 700476 was evident. When wild-type cells were grown on succinate in the presence of uracil or orotic acid, the activities of all 5 pyrimidine biosynthetic enzymes were depressed while the activities of 3 of the enzymes decreased in glucose-grown cells supplemented with uracil or orotic acid compared with unsupplemented cells. Pyrimidine limitation of succinate- or glucose-grown pyrimidine auxotrophic cells lacking orotate phosphoribosyltransferase activity resulted in more than a doubling of the pyrimidine biosynthetic enzyme activities relative to their activities in uracil-grown cells.

Fungal production of the polysaccharide pullulan from a plant hydrolysate.

The ability of the fungus Aureobasidium pullulans ATCC 42023 to produce pullulan from hydrolysates of the native grass known as prairie cordgrass was investigated and examined relative to polysaccharide and cell biomass production, yield, and pullulan content of the polysaccharide. A pullulan concentration of 9.7 g l-1 and yield of 0.

A Candida guilliermondii lysine hyperproducer capable of elevated citric acid production.

A mutant of the yeast Candida guilliermondii ATCC 9058 exhibiting elevated citric acid production was isolated based upon its ability to overproduce lysine. This method involved the use of a solid medium containing a combination of lysine analogues to identify a mutant that produced a several-fold higher lysine level compared to its parent strain using glucose or glycerol as a carbon source. The mutant strain was also capable of producing more than a fivefold higher citric acid level on glycerol as a carbon source compared to its parent strain.

Fungal biotransformation of crude glycerol into malic acid.

Malic acid production from the biodiesel coproduct crude glycerol by Aspergillus niger ATCC 9142, ATCC 10577 and ATCC 12846 was observed to occur with the highest malic acid level acid being produced by A. niger ATCC 12846. Fungal biomass production from crude glycerol was similar, but ATCC 10577 produced the highest biomass.

Effect of nitrogen source concentration on curdlan production by Agrobacterium sp. ATCC 31749 grown on prairie cordgrass hydrolysates.

The effect of nitrogen source concentration on the production of the polysaccharide curdlan by the bacterium Agrobacterium sp. ATCC 31749 from hydrolysates of prairie cordgrass was examined. The highest curdlan concentrations were produced by ATCC 31749 when grown on a medium containing a solids-only hydrolysate and the nitrogen source ammonium phosphate (2.

Pyrimidine nucleotide synthesis in Pseudomonas nitroreducens and the regulatory role of pyrimidines.

Control of pyrimidine biosynthesis in the commercially important, hydrocarbon-utilizing bacterium Pseudomonas nitroreducens ATCC 33634 was investigated. When glucose-grown wild-type cells were supplemented with uracil or orotic acid, the pyrimidine biosynthetic activities were depressed. Pyrimidine limitation of glucose-grown cells of an orotate phosphoribosyltransferase mutant caused aspartate transcarbamoylase and dihydroorotase activities to increase by about 4-fold while the other enzyme activities about doubled.

Production of the polysaccharide curdlan by an Agrobacterium strain grown on a plant biomass hydrolysate.

Production of the commercially available polysaccharide curdlan by Agrobacterium sp. strain ECP-1, isolated as a mutant strain from ATCC 31749, on a medium containing a hydrolysate of the plant prairie cordgrass with selected ammonium phosphate concentrations was investigated for a period of 144 h. Although several ammonium phosphate concentrations supported curdlan production by the strain, the optimal concentration after 120 or 144 h was 3.

Elevated 3-hydroxypropionaldehyde production from glycerol using a Citrobacter freundii mutant.

A mutant strain of Citrobacter freundii capable of elevated 3-hydroxypropionaldehyde production from glycerol was isolated using chemical mutagenesis and a screening protocol. The protocol involved screening mutagenized bacterial cells on solid minimal medium containing 5 % (v/v) glycerol. Colonies were picked onto duplicate solid minimal medium plates and one plate was stained with 1 % (w/v) phloroglucinol.

Citric acid production by Candida species grown on a soy-based crude glycerol.

Citric acid was produced by five species of the yeast Candida after growth on a medium containing soy biodiesel-based crude glycerol. After growth on a medium containing 10 g L(-1) or 60 g L(-1) crude glycerol for 168 hr at 30°C, Candida parapsilosis ATCC 7330 and C. guilliermondii ATCC 9058 produced the highest citric acid levels.

Pullulan Production by Aureobasidium pullulans ATCC 201253 Cells Adsorbed onto Cellulose Anion and Cation Exchangers.

The anion exchanger phosphocellulose and the cation exchanger triethylaminoethyl cellulose were used to immobilize cells of the fungus Aureobasidium pullulans ATCC 201253 and the adsorbed cells were subsequently investigated for their ability to produce the polysaccharide pullulan using batch fermentation. The cells adsorbed on the triethylaminoethyl cellulose at pH 7.5 produced higher pullulan levels than those cells immobilized on phosphocellulose at pH 4.

Pyrimidine biosynthesis in Pseudomonas veronii and its regulation by pyrimidines.

Pyrimidine biosynthesis in the nutritionally versatile bacterium Pseudomonas veronii ATCC 700474 appeared to be controlled by pyrimidines. When wild type cells were grown on glucose in the presence of uracil, four enzyme activities were depressed while all five enzyme activities increased in succinate-grown cells supplemented with uracil. Independent of carbon source, orotic acid-grown cells elevated aspartate transcarbamoylase, dihydroorotase, orotate phosphoribosyltransferase or OMP decarboxylase activity.

Malic acid production from thin stillage by Aspergillus species.

The ability of Aspergillus strains to utilize thin stillage to produce malic acid was compared. The highest malic acid was produced by Aspergillus niger ATCC 9142 at 17 g l(-1). Biomass production from thin stillage was similar with all strains but ATCC 10577 was the highest at 19 g l(-1).

Pullulan production by Aureobasidium pullulans cells immobilized in chitosan beads. Fungal pullulan production by immobilized cells.

Fungal cells of Aureobasidium pullulans ATCC 201253 were immobilized by entrapment in chitosan beads, and the immobilized cells were investigated for their ability to produce the polysaccharide pullulan using batch fermentation. The 1% chitosan-entrapped fungal cells were capable of producing pullulan for two cycles of 168 h using corn syrup as a carbon source. Pullulan production by the immobilized cells increased by 1.

Effect of carbon source on polysaccharide production by alginate-entrapped Aureobasidium pullulans ATCC 42023 cells.

The production of the exopolysaccharide pullulan using entrapped cells of the fungus Aureobasidium pullulans ATCC 42023 was investigated relative to carbon source. Fungal cells grown on glucose or sucrose as a carbon source were entrapped in calcium alginate beads and found to be capable of synthesizing the polysaccharide for two production cycles. Using 2.

Effect of carbon source on pyrimidine biosynthesis in Pseudomonas oryzihabitans.

The effect of carbon source on the regulation of pyrimidine biosynthesis in the opportunistic human pathogen Pseudomonas oryzihabitans was studied at the level of enzyme synthesis. Although pyrimidine supplementation of glucose-grown Ps. oryzihabitans cells produced a slight but statistically significant effect on the de novo pyrimidine biosynthetic pathway enzyme activities, catabolite repression of the enzyme activities by glucose appeared to be occurring.

Control of pyrimidine nucleotide formation in Pseudomonas fulva.

Control of pyrimidine formation was examined in Pseudomonas fulva ATCC 31418. Pyrimidine supplementation lowered pyrimidine biosynthetic pathway enzyme activities in cells grown on glucose or succinate as a carbon source indicating possible repression of enzyme synthesis. Pyrimidine limitation experiments were conducted using an orotidine 50-monophosphate decarboxylase mutant strain isolated in this study.

Elevated curdlan production by a mutant of Agrobacterium sp. ATCC 31749.

A mutant strain of the curdlan-producing bacterium Agrobacterium sp. ATCC 31749, isolated by ethylmethane sulfonate mutagenesis and resistance to ampicillin, was capable of elevated curdlan synthesis. Using 2.

Regulation of pyrimidine formation in Pseudomonas lundensis.

The regulation of pyrimidine formation in the food spoilage agent Pseudomonas lundensis ATCC 49968 by pyrimidines was examined. In P. lundensis cells grown on glucose as a carbon source, the enzymes aspartate transcarbamoylase, dihydroorotase, and orotidine 5'-monophosphate decarboxylase were induced by orotic acid.

Curdlan production by Agrobacterium sp. ATCC 31749 on an ethanol fermentation coproduct.

The production of the polysaccharide curdlan from the ethanol processing coproduct condensed corn distillers solubles by the bacterium Agrobacterium sp. ATCC 31749 was investigated. It was found that curdlan could be produced by the bacterium using condensed corn distillers solubles as a source of carbon and nitrogen.