Lamosa Pedro, Lourenço Eva C, d'Avó Filipa, Nobre Ana, Bandeiras Tiago M, da Costa Milton S, Ventura M Rita, Santos Helena
Instituto de Tecnologia Química e Biológica, Universidade Nova de Lisboa, Av. da República-EAN, Apartado 127, 2780-157, Oeiras, Portugal,
Extremophiles. 2015 Mar;19(2):373-82. doi: 10.1007/s00792-014-0723-0. Epub 2015 Jan 3.
The solute pool of the actinobacterium Rubrobacter xylanophilus has been investigated as a function of the growth temperature and concentration of NaCl in the medium (Empadinhas et al. Extremophiles 11: 667-673, 2007). Changing the carbon source from glucose to maltose in a minimal growth medium led to the accumulation of an unknown organic compound whose structure was investigated by NMR and confirmed by chemical synthesis in the present study as: (2R)-2-(1-O-α-D-mannopyranosyl)-3-(1-O-α-D-glucopyranosyl)-D-glycerate (MGlyG). In addition to this newly identified diglycoside, the solute pool of R. xylanophilus included trehalose, mannosylglycerate, di-myo-inositol phosphate and di-N-acetyl-glucosamine phosphate. The structure of MGlyG was established by NMR and confirmed by chemical synthesis. The availability of g-amounts of the synthetic material allowed us to perform stabilization tests on three model enzymes (malate dehydrogenase, staphylococcal nuclease, and lysozyme), and compare the efficacy of MGlyG with other natural glyceryl glycosides, such as α-D-mannosyl-D-glycerate, α-D-glucosyl-D-glycerate and α-D-glucosyl-(1 → 6)-α-D-glucosyl-(1 → 2)-D-glycerate.
嗜热放线菌嗜木栖红红球菌的溶质池已作为培养基中生长温度和氯化钠浓度的函数进行了研究（恩帕迪尼亚斯等人，《极端微生物》11: 667 - 673，2007年）。在基本生长培养基中将碳源从葡萄糖改为麦芽糖会导致一种未知有机化合物的积累，本研究通过核磁共振对其结构进行了研究，并通过化学合成确认为：(2R)-2-(1-O-α-D-甘露吡喃糖基)-3-(1-O-α-D-葡萄糖吡喃糖基)-D-甘油酸酯（MGlyG）。除了这种新鉴定的二糖苷外，嗜木栖红红球菌的溶质池还包括海藻糖、甘露糖基甘油酸、二-肌醇磷酸酯和二-N-乙酰葡糖胺磷酸酯。MGlyG的结构通过核磁共振确定，并通过化学合成得到证实。合成材料的克量可用性使我们能够对三种模型酶（苹果酸脱氢酶、葡萄球菌核酸酶和溶菌酶）进行稳定性测试，并将MGlyG与其他天然甘油基糖苷（如α-D-甘露糖基-D-甘油酸酯、α-D-葡萄糖基-D-甘油酸酯和α-D-葡萄糖基-(1→6)-α-D-葡萄糖基-(1→2)-D-甘油酸酯）的功效进行比较。
