Semino C E, Dankert M A
Instituto de Investigaciones Bioquímicas Fundación Campomar, Facultad de Ciencias Exactas y Naturales y CONICET, Buenos Aires, Argentina.
Cell Mol Biol (Noisy-le-grand). 1994 Nov;40(7):1029-37.
Rhizobium meliloti associates symbiotically with alfalfa by forming root nodules in which the bacteria reduce atmospheric N2 into products useful to both organisms. Nod factors are signal molecules, lipooligosaccharides, produced by the bacteria that trigger nodule formation in the plant host. Nod Rm-1 consists of a beta-1,4-N-acetyl glucosamine tetrasaccharide from which the N-acetyl group at the non reducing end is replaced by a fatty acid and the N-acetyl glucosamine at the reducing end is sulfated at position 6. By in vitro incubation of electroporated cells in the presence of [35S]PAPS or UDP-[14C]GlcNAc a labelled compound has been obtained with the properties of the in vivo produced Nod Rm-1 factor, as judged by HPLC, TLC and HPTLC techniques. The [14C]GlcNAc labelled compound has also hair root deformation activity on alfalfa plantlets indicating that a functional Nod Rm-1 factor has been synthesized in vitro.
苜蓿中华根瘤菌通过形成根瘤与苜蓿共生，在根瘤中细菌将大气中的N2还原为对两种生物都有用的产物。结瘤因子是由细菌产生的信号分子脂寡糖，可触发植物宿主中的结瘤形成。结瘤Rm-1由β-1,4-N-乙酰葡糖胺四糖组成，其中非还原端的N-乙酰基被脂肪酸取代，还原端的N-乙酰葡糖胺在6位被硫酸化。通过在[35S]PAPS或UDP-[14C]GlcNAc存在下对电穿孔细胞进行体外孵育，获得了一种具有体内产生的结瘤Rm-1因子特性的标记化合物，这是通过HPLC、TLC和HPTLC技术判断的。[14C]GlcNAc标记的化合物对苜蓿幼苗也有发根变形活性，表明在体外已合成了功能性的结瘤Rm-1因子。
