Compatible solutes in representatives of the genera Brevibacterium and Corynebacterium : Occurrence of tetrahydropyrimidines and glutamine

The aim of our investigation was to study the haloadaptation of a number of species of Gram-positive bacteria belonging to the genera Brevibacterium and Corynebacterium. We used two different HPLC-techniques and 13C-NMR spectroscopy for the identification of osmolytes (compatible solutes). The tetrahydropyrimidines (‘ectoines’) are the main compatible solutes in the genus Brevibacterium, whereas accumulation of glycine-betaine and accumulation of synthesis of glutamine is mainly responsible for osmoadaptation in the genus Corynebacterium. Pipecolic acid, formerly described as a potential osmolyte synthesized de novo in C. ammoniagenes, does not contribute markedly to the solute pool, unless supplemented to the medium.