| Popis: |
SUMMARY: Cultures of 351 miscellaneous Gram-negative rods including 54 pseudomonads were tested for their capacity to break down arginine rapidly by Moller's qualitative technique, by a new qualitative method, and by a quantitative technique which uses standardized washed suspensions. All but 5 of the pseudomonads gave positive results by both qualitative techniques. Among the other organisms tested, positive results were given by Aeromonas strains, some Cloaca strains, some Salmonellas, and, in the case of the new qualitative technique, by 5 strains among other groups. With the quantitative technique 50% of the arginine was broken down in 2 hr. by all but one of the pseudomonads as compared with only four strains among the other groups. The arginine was broken down completely by 49 of the 54 pseudomonads, but by no other organisms. The ability to break down arginine rapidly is a useful taxonomic feature for pseudomonads and the qualitative tests may have practical value in the identification of strains which do not produce pigment. |
