Studies on The Nitrogen Metabolism of Plants VII. Toxicity of Some Oximes and Oximino·Acids to Azotobacter and Their Utilization

Abstract

22 oximino derivatives were synthesized; they included ketoximes, dioximes, oximino-monocarboxylic acids, and oximino-dicarboxylic acids and esters of the last 2 groups of compounds. Toxicity of these compounds to Azotobacter was measured; esters, dioximes, and alpha-oximino-dicarboxylic acids were non-toxic at 5 x 10-3[image] concn., while the other oximino-derivatives were toxic at about 5 x 10-4[image]. Toxicity was related to chemical structure and probable orientation in relation to membrane surfaces. Azotobacter readily uses both cis- and trans-modifications of both oximinosuccinic and alpha-oximinoglutaric acids as source of N at pH 6.8 in absence of atmospheric N or other source of N. The possibility that these 2 oximino-acids might be intermediates in nitrate metabolism is discussed.