Divergent genes in potential inoculant Sinorhizobium strains are related to DNA replication, recombination, and repair

Abstract

To serve as inoculants of legumes, nitrogen-fixing rhizobium strains should be competitive and tolerant of diverse environments. We hybridized the genomes of symbiotically efficient and salt tolerant Sinorhizobium inoculant strains onto the Sinorhizobium meliloti Rm1021 microarray. The number of variable genes, that is, divergent or putatively multiplied genes, ranged from 503 to 1556 for S. meliloti AK23, S. meliloti STM 1064 and S. arboris HAMBI 1552. The numbers of divergent genes affiliated with the symbiosis plasmid pSymA and related to DNA replication, recombination and repair were significantly higher than expected. The variation was mainly in the accessory genome, implying that it was important in shaping the adaptability of the strains.

A COMPARATIVE ANALYSIS OF GENOMIC CHARACTERS OF REFERENCE Sinorhizobium meliloti STRAINS, THE ALFALFA SYMBIONTS (review)

“…A fundamentally different approach is to create a system for genetic monitoring of the stability of economically valuable strains and to study the pangenome of nodule bacteria of alfalfa and the microbiome of agroecosystems [9][10][11]. The comparison of the genomic characteristics of symbiotic active strains will allow identifying functionally important marker sequences and can become the basis for creating such a system [12]. One of the stages of this study is a comparison of the properties of production strains that can be recommended as model in the development of a system for monitoring the stability of agroecosystems.…”