Arginine Deiminase Activity Research Articles

Intracellular localization of the arginine deiminase pathway inStreptococcus mitis

A subcellular fractionation study was carried out onStreptococcus mitis ATCC 9811 to determine the location of the arginine deiminase pathway. Arginine deiminase activity was detected in the cell wall fraction, ornithine carbamoyltransferase activity was recovered in both the cell wall and cytoplasmic fractions, and carbamate kinase activity was detected in the cytoplasmic fraction.

Arginine metabolism in lactic streptococci.

Streptococcus lactis metabolizes arginine via the arginine deiminase pathway producing ornithine, ammonia, carbon dioxide, and ATP. In the four strains of S. lactis examined, the specific activities of arginine deiminase and ornithine transcarbamylase were 5- to 10-fold higher in galactose-grown cells compared with glucose- or lactose-grown cells. The addition of arginine increased the specific activities of these two enzymes with all growth sugars. The specific activity of the third enzyme involved in arginine metabolism (carbamate kinase) was not altered by the composition of the growth medium. In continuous cultures arginine deiminase was not induced, and arginine was not metabolized, until glucose limitation occurred. In batch cultures the metabolism of glucose and arginine was sequential, whereas galactose and arginine were metabolized concurrently, and the energy derived from arginine metabolism was efficiently coupled to growth. No arginine deiminase activity was detected in the nine Streptococcus cremoris strains examined, thus accounting for their inability to metabolize arginine. All nine strains of S. cremoris had specific activities of carbamate kinase similar to those found in S. lactis, but only five S. cremoris strains had ornithine transcarbamylase activity.

Mapping of the arginine deiminase gene in Pseudomonas aeruginosa.

A mutant of Pseudomonas aeruginosa PAO lacking arginine deiminase activity (arcA) was isolated by screening for a derivative of an arcB mutant (deficient in catabolic ornithine carbamoyltransferase) that did not excrete citrulline under conditions of limited aeration. The arcA mutation was highly cotransducible with arcB.

OCCURRENCE OF ENZYMES OF ARGININE DIHYDROLASE PATHWAY IN SPIROPLASMA CITRI

Cell-free extract of California strain of Spiroplasma cirri contained activities of arginine deiminase, ornithine transcarbamylase, and carbamyl phosphokinase but not those of argininosuccinic acid sythetase, argininosuccinase, and arginase. When washed cells suspended in buffer were supplied with arginine, the disappearance of arginine was accompanied by appearance of citrulline, ornithine, and ammonia. Addition of rifampicin or cycloheximide to culture medium at the time of inoculation prevented the appearance of activity of arginine deiminase, the first enzyme of arginine dihydrolase pathway. These results show that arginine degradation in S. citri is via arginine dihydrolase pathway and that arginine deiminase, and possibly the other two enzymes of this pathway, are inducible.

Regulation of the arginine dihydrolase pathway in Clostridium sporogenes

Arginine deiminase activity was induced during the vegetative growth of Clostridium sporogenes. The enzyme was sensitive to catabolite repression. The other enzymes of the arginine dihydrolase pathway, namely, ornithine carbamoyl-transferase and carbamate kinase, did not show such variation.

Role of arginine deiminase in growth of Mycoplasma hominis.

Arginine has been considered as the major energy source of nonglycolytic arginine-utilizing mycoplasmata. When three strains of Mycoplasma arginini, and one strain each of Mycoplasma arthritidis, Mycoplasma fermentans, Mycoplasma gallinarum, Mycoplasma gallisepticum and Mycoplasma hominis were grown in the medium with high arginine concentration (34 mM) compared with low arginine (4 mM), both the protein content of the organisms and the specific activity of arginine deiminase increased. M. fermentans, the one arginine-utilizing species included in the survey which is also glycolytic, showed an increase in protein content but no increase in specific activity of the enzyme. The glycolytic non-arginine-utilizing M. gallisepticum did not show an increase in either parameter. The Km for arginine deiminase from crude cell extracts was 1.66 X 10(-4)M. The enzyme demonstrated a hyperbolic activation curve subject to substrate inhibition and was not affected by the presence of L-histidine. When mycoplasmic protein and arginine deiminase were determined for M. hominis under aerobic and anaerobic conditions, aerobically grown cells exhibited no detectable enzymatic increases until late in log phase. Higher levels of arginine deiminase were observed earlier in the anaerobic growth cycle. The rate of 14CO2 evolution from [guanido-14C]arginine was not altered in arginine-supplemented cells compared with cells grown in low arginine. In addition, CO2 production did not parallel increased arginine deiminase activity. These observations argue that arginine is used only as an alternate energy source in these organisms.

The duplication of arginine catabolism and the meaning of the two ornithine carbamoyltransferases in [formula omitted

Arginine deiminase and carbamate kinase activities are shown to be present in cell-free extracts of Bacillus licheniformis . This gives the rationale for the occurrence of an arginine-inducible ornithine carbamoyltransferase in this organism and suggests that, in vivo and under the proper conditions, this enzyme is able to catalyze the phosphorolysis of citrulline. This also shows that this Bacillus species has two arginine catabolic pathways. This duplication appears to be under the control of O 2.

Arginine metabolism in mycoplasma and infected strain L-929 fibroblasts

Strain L-929 fibroblasts normally utilize HCO 3 − for the synthesis of their nucleic acid pyrimidines. When infected with Mycoplasma oralis 3 3 A common mycoplasma contaminant of metazoan cells distributed by commercial supply houses. This strain has been identified as M. oralis for us by Dr. R. M. Chanock and Dr. M. L. Somerson, National Institute of Allergy and Infectious Diseases, Bethesda, Maryland. , however, the enzymes arginine deiminase and ornithine transcarbamylase (OTC) are acquired and the guanidino carbon of arginine is utilized in place of HCO 3 − . The pathway of arginine incorporation is via citrulline, carbamylphosphate, and carbamylaspartate. Although pure cultures of M. oralis or hominis possess arginine deiminase and ornithine transcarbamylase activities, neither of these mycoplasma are able to synthesize orotic acid from ureido-C 14 citrulline. It is concluded from these studies that the synthesis of pyrimidines from arginine in M. oralis infected strain L-929 fibroblast cell cultures requires the coordinate utilization of the carbamyl phosphate synthesizing enzymes from the infecting organism and the pyrimidine synthesizing enzymes of the host cell. The metabolism of M. hominis and T-strain Mycoplasma are compared with and contrasted to M. oralis.

A Rapid Chemical Method for Detecting PPLO Contamination of Tissue Cell Cultures

A rapid, simple and routine chemical method for detection of PPLO contamination in cell cultures is reported. The method is based on the presence of arginine deiminase activity in all tissue culture PPLO strains, but absence from all mammalian tissue and PPLO-free cell cultures. In a total of 73 cell cultures examined, the detection of PPLO determined by presence of arginine deiminase activity agreed entirely with the most sensitive cultural procedure which requires 14 days.