Kijne J W, Smit G, Díaz C L, Lugtenberg B J
Department of Plant Molecular Biology, Leiden University, The Netherlands.
J Bacteriol. 1988 Jul;170(7):2994-3000. doi: 10.1128/jb.170.7.2994-3000.1988.
The ability of Rhizobium leguminosarum 248 to attach to developing Pisum sativum root hairs was investigated during various phases of bacterial growth in yeast extract-mannitol medium. Direct cell counting revealed that growth of the rhizobia transiently stopped three successive times during batch culture in yeast extract-mannitol medium. These interruptions of growth, as well as the simultaneous autoagglutination of the bacteria, appeared to be caused by manganese limitation. Rhizobia harvested during the transient phases of growth inhibition appeared to have a better attachment ability than did exponentially growing rhizobia. The attachment characteristics of these manganese-limited rhizobia were compared with those of carbon-limited rhizobia (G. Smit, J. W. Kijne, and B. J. J. Lugtenberg, J. Bacteriol. 168:821-827, 1986, and J. Bacteriol. 169:4294-4301, 1987). In contrast to the attachment of carbon-limited cells, accumulation of manganese-limited rhizobia (cap formation) was already in full progress after 10 min of incubation; significantly delayed by 3-O-methyl-D-glucose, a pea lectin haptenic monosaccharide; partially resistant to sodium chloride; and partially resistant to pretreatment of the bacteria with cellulase. Binding of single bacteria to the root hair tips was not inhibited by 3-O-methyl-D-glucose. Whereas attachment of single R. leguminosarum cells to the surface of pea root hair tips seemed to be similar for both carbon- and manganese-limited cells, the subsequent accumulation of manganese-limited rhizobia at the root hair tips is apparently accelerated by pea lectin molecules. Moreover, spot inoculation tests with rhizobia grown under various culture conditions indicated that differences in attachment between manganese- and carbon-limited R. leguminosarum cells are correlated with a significant difference in infectivity in that manganese-limited rhizobia, in contrast to carbon-limited rhizobia, are infective. This growth-medium-dependent behavior offers and explanation for the seemingly conflicting data on the involvement of host plant lectins in attachment of rhizobia to root hairs of leguminous plants. Sym plasmid-borne genes do not play a role in manganese-limitation-induced attachment of R. leguminosarum.
在酵母提取物 - 甘露醇培养基中细菌生长的不同阶段，研究了豌豆根瘤菌248附着于发育中的豌豆根毛的能力。直接细胞计数显示，在酵母提取物 - 甘露醇培养基中进行分批培养时，根瘤菌的生长连续三次短暂停止。这些生长中断以及细菌同时发生的自凝现象，似乎是由锰限制引起的。在生长抑制的短暂阶段收获的根瘤菌，其附着能力似乎比指数生长的根瘤菌更好。将这些受锰限制的根瘤菌的附着特性与受碳限制的根瘤菌（G. Smit、J. W. Kijne和B. J. J. Lugtenberg，《细菌学杂志》168:821 - 827，1986年，以及《细菌学杂志》169:4294 - 4301，1987年）的附着特性进行了比较。与受碳限制的细胞的附着情况不同，受锰限制的根瘤菌（帽形成）在孵育10分钟后就已经在充分进行；被3 - O - 甲基 - D - 葡萄糖（一种豌豆凝集素半抗原单糖）显著延迟；对氯化钠部分抗性；并且对用纤维素酶预处理细菌部分抗性。单个细菌与根毛尖端的结合不受3 - O - 甲基 - D - 葡萄糖的抑制。虽然对于受碳限制和受锰限制的细胞，单个豌豆根瘤菌细胞附着于豌豆根毛尖端表面的情况似乎相似，但随后受锰限制的根瘤菌在根毛尖端的积累显然被豌豆凝集素分子加速。此外，用在各种培养条件下生长的根瘤菌进行的点接种试验表明，受锰限制和受碳限制的豌豆根瘤菌细胞在附着方面的差异与感染性的显著差异相关，即与受碳限制的根瘤菌不同，受锰限制的根瘤菌具有感染性。这种依赖于生长培养基的行为为关于宿主植物凝集素在根瘤菌附着于豆科植物根毛过程中所起作用的看似相互矛盾的数据提供了解释。共生质粒携带的基因在受锰限制诱导的豌豆根瘤菌附着过程中不起作用。
