Utilization of 2-aminoethylarsonic acid in Pseudomonas aeruginosa

• Published in: Journal of general microbiology Vol. 138; no. 6; pp. 1283 - 1287
• Main Authors: Lacoste, Anne-Marie, Dumora, Catherine, Ali, Bassam R. S, Neuzil, Eugene, Dixon, Henry B. F
• Format: Journal Article
• Language: English
• Published: England Soc General Microbiol 01.06.1992
• Subjects: Aminoethylphosphonic Acid - metabolism; Arsenic Poisoning; Arsenicals - metabolism; Biological Transport - drug effects; Cell Division - drug effects; Hydrolases - metabolism; Pseudomonas aeruginosa - metabolism; Pyruvates - metabolism
• ISSN: 0022-1287
• DOI: 10.1099/00221287-138-6-1283

1 Departement de Biochimie et de Biologie moléculaire, Université de Bordeaux II, 146 rue Léo-Saignat, 33076 Bordeaux Cedex, France 2 Department of Biochemistry, University of Cambridge, Tennis Court Road, Cambridge CB2 1QW, UK * Author for correspondence. Tel. 57 57 13 74; fax 56 99 03 80. ABSTRACT This paper describes the metabolism, transport and growth inhibition effects of 2-aminoethylarsonic acid (AEA) and 3-aminopropylarsonic acid (APrA). The former compound supported growth of Pseudomonas aeruginosa , as sole nitrogen source. The two arsonates inhibited the growth of this bacterium when 2-aminoethylphosphonic acid (AEP) but not alanine or NH 4 Cl, was supplied as the only other nitrogen source. The analogy between AEA and the natural compound AEP led us to examine the in vitro and in vivo interaction of AEA with the enzymes of AEP metabolism. The uptake system for AEP ( K m 6 µM) was found to be competitively inhibited by AEA and APrA ( K i 18 µM for each). AEP-aminotransferase was found to act on AEA with a K m of 4 mM (3.85 mM for AEP). Alanine and 2-arsonoacetaldehyde were generated concomitantly, in a stoichiometric reaction. In vivo , AEA was catabolized by the AEP-aminotransferase since it was able to first induce this enzyme, then to be an efficient substrate. The lower growth observed may have been due to the slowness with which the permease and the aminotransferase were induced, and hence to a poor supply of alanine by transamination.