Agricultural Research Council, Plant Health and Protection (ARC-PHP), Private Bag X134, Pretoria 0121, South Africa.
Department of Plant and Soil Sciences, Faculty of Science, Engineering and Agriculture, University of Venda, Private Bag X5050, Thohoyandou 0950, South Africa.
Genes (Basel). 2023 May 14;14(5):1084. doi: 10.3390/genes14051084.
The symbiotic fixation of atmospheric nitrogen (N) in root nodules of tropical legumes such as pigeonpea () is a complex process, which is regulated by multiple genetic factors at the host plant genotype microsymbiont interface. The process involves multiple genes with various modes of action and is accomplished only when both organisms are compatible. Therefore, it is necessary to develop tools for the genetic manipulation of the host or bacterium towards improving N fixation. In this study, we sequenced the genome of a robust rhizobial strain, '10ap3' that was compatible with pigeonpea, and we determined its genome size. The genome consisted of a large circular chromosome (6,297,373 bp) and contained 6013 genes of which 99.13% were coding sequences. However only 5833 of the genes were associated with proteins that could be assigned to specific functions. The genes for nitrogen, phosphorus and iron metabolism, stress response and the adenosine monophosphate nucleoside for purine conversion were present in the genome. However, the genome contained no common genes, suggesting that an alternative pathway involving a purine derivative was involved in the symbiotic association with pigeonpea.
豆科植物根瘤中固氮共生体（）将大气中的氮固定是一个复杂的过程，该过程受到宿主植物基因型-微生物共生体界面的多个遗传因素的调控。这个过程涉及多种具有不同作用模式的基因，只有当两种生物相容时才能完成。因此，有必要开发用于宿主或细菌遗传操作的工具，以提高固氮作用。在这项研究中，我们对与豆科植物相容的强根瘤菌菌株 10ap3 进行了基因组测序，并确定了其基因组大小。该基因组由一个大的圆形染色体（6297373bp）组成，包含 6013 个基因，其中 99.13%是编码序列。然而，只有 5833 个基因与可以分配到特定功能的蛋白质相关。氮、磷和铁代谢、应激反应以及嘌呤转化的腺苷一磷酸核苷的基因都存在于基因组中。然而，基因组中没有共同的基因，这表明与豆科植物共生关系涉及嘌呤衍生物的替代途径。
