On Amino Acid Decarboxylases of Salmonella Types and on the KCN Test

Abstract

In a preceding paper by Meller (1) an account was given of the manometric determination of decarboxylases of lysine, arginine, ornithine an'd glutamic acid. In a subsequent work, Meller ( 2 ) reported his experiences with representatives of the most frequent groups of Enterobacteriaceae and various intermediate cultures. He examined a total of 671 cultures that were grown in tryptic digest of casein. Determination of the decarboxylases was performed by employment of a simplified method, in which the washed bacterial suspensions were shaken with toluene, and then the changes in pH after incubation of the mixtures of bacteria, amino acids and buffer were determined by means of indicator.In a following work-entitled "Simplified tests for some amino acid decarboxylases and for the arginine dihydrolase system"-Meller ( 3 ) showed that the anaerobic decomposition of amino acid by bacteria can be demonstrated in the following simple way: The bacteria are grown in nutritionally adequate media to which amino acids and indicator are added, and which are covered with a layer of paraffin oil. For particular details the reader is referred to the above-mentioned paper. By means of this method M d e r obtained specific reactions for decarboxylases of lysine, ornithine and glutamic acid. On determination of arginine decarboxylases a reaction was obtained that was brought about either by arginine decarboxylases or by the arginine dihydrolase system (arginine desimidase and citrulline ureidase), or by both.

A novel extracellular low‐temperature active phytase from Bacillus aryabhattai RS1 with potential application in plant growth

“…The production of the phytohormone indole 3‐acetic acid (IAA) was determined by using Salkowski's reagent as described by Patten and Glick . Ammonia production was quantified by using Nessler's reagent . For hydrogen cyanide (HCN) production the method of Bakker and Schippers was used .…”

“…26 Ammonia production was quantified by using Nessler's reagent. 27 For hydrogen cyanide (HCN) production the method of Bakker and Schippers was used. 28 Siderophore production was determined by using blue indicator dye and chrome azurol S agar.…”

Exploring the efficacy of tryptone-stabilized silver nanoparticles against respiratory tract infection-causing bacteria: a study on planktonic and biofilm forms

“…A 100 µl of bacterial supernatant was incubated with 50 µl of urea (substrate) for 3 h at 37 • C. After incubation, 10 µl of Nessler's reagent was added to the wells and incubated for 5 min. The amount of urease activity was quantified spectrophotometrically at 530 nm [54,72].…”