Jebbar M, Champion C, Blanco C, Bonnassie S
Département Membranes et Osmorégulation, Laboratoire de Génétique et Physiologie microbiennes, CNRS UPRES A 6026, Université de Rennes I, France.
Res Microbiol. 1998 Mar;149(3):211-9. doi: 10.1016/s0923-2508(98)80081-8.
Carnitine is a trimethyl amino acid found at relatively high concentrations in materials of animal origin. Exogenously provided L-carnitine was found to stimulate growth of Brevibacterium linens ATCC 19391 in media with inhibitory osmotic strength. Its osmoprotective ability was as potent as that of glycine betaine. Electrophoretic and spectroscopic (NMR) analysis showed that this compound is only transiently accumulated, but in significant amounts, by B. linens under hyperosmotic stress and is converted into glycine betaine. The L-carnitine/glycine betaine pathway is inducible by L-carnitine in B. linens. The D-enantiomer did not improve growth of B. linens, even though this solute is accumulated by B. linens at the same level as glycine betaine. The two isomeric forms of carnitine repress the build-up of ectoine, the main endogenous osmolyte in B. linens.
肉碱是一种三甲基氨基酸，在动物源材料中含量相对较高。研究发现，外源性提供的左旋肉碱可刺激亚麻短杆菌ATCC 19391在具有抑制性渗透压强度的培养基中生长。其渗透保护能力与甘氨酸甜菜碱相当。电泳和光谱（核磁共振）分析表明，该化合物在高渗胁迫下仅被亚麻短杆菌短暂但大量积累，并转化为甘氨酸甜菜碱。左旋肉碱/甘氨酸甜菜碱途径可被亚麻短杆菌中的左旋肉碱诱导。D-对映体并不能促进亚麻短杆菌的生长，尽管这种溶质在亚麻短杆菌中的积累水平与甘氨酸甜菜碱相同。肉碱的两种异构体形式会抑制亚麻短杆菌中主要内源性渗透调节物质依克多因的积累。
