<i>Ensifer meliloti</i> L6-AK89, an Effective Inoculant of <i>Medicago lupulina</i> Varieties: Phenotypic and Deep-Genome Screening
Marina L. Roumiantseva,
Maria E. Vladimirova,
Alla S. Saksaganskaia,
Victoria S. Muntyan,
Alexandra P. Kozlova,
Alexey M. Afonin,
Olga A. Baturina,
Boris V. Simarov
Affiliations
Marina L. Roumiantseva
Laboratory of Genetics and Selection of Microorganisms, Federal State Budget Scientific Institution, All-Russia Research Institute for Agricultural Microbiology (FSBSI ARRIAM), 196608 Saint Petersburg, Russia
Maria E. Vladimirova
Laboratory of Genetics and Selection of Microorganisms, Federal State Budget Scientific Institution, All-Russia Research Institute for Agricultural Microbiology (FSBSI ARRIAM), 196608 Saint Petersburg, Russia
Alla S. Saksaganskaia
Laboratory of Genetics and Selection of Microorganisms, Federal State Budget Scientific Institution, All-Russia Research Institute for Agricultural Microbiology (FSBSI ARRIAM), 196608 Saint Petersburg, Russia
Victoria S. Muntyan
Laboratory of Genetics and Selection of Microorganisms, Federal State Budget Scientific Institution, All-Russia Research Institute for Agricultural Microbiology (FSBSI ARRIAM), 196608 Saint Petersburg, Russia
Alexandra P. Kozlova
Laboratory of Genetics and Selection of Microorganisms, Federal State Budget Scientific Institution, All-Russia Research Institute for Agricultural Microbiology (FSBSI ARRIAM), 196608 Saint Petersburg, Russia
Alexey M. Afonin
Laboratory of Genetics of Plant-Microbe Interactions, Federal State Budget Scientific Institution, All-Russia Research Institute for Agricultural Microbiology (FSBSI ARRIAM), 196608 Saint Petersburg, Russia
Olga A. Baturina
Institute of Chemical Biology and Fundamental Medicine, Siberian Branch of the Russian Academy of Sciences (ICBFM SB RAS), 630090 Novosibirsk, Russia
Boris V. Simarov
Laboratory of Genetics and Selection of Microorganisms, Federal State Budget Scientific Institution, All-Russia Research Institute for Agricultural Microbiology (FSBSI ARRIAM), 196608 Saint Petersburg, Russia
This paper presents a deep analysis of the accessory genome of an economically promising strain of Ensifer (Sinorhizobium) meliloti, L6-AK89, obtained as a result of next-generation high-throughput sequencing (MiSeq, MinIon). Strain L6-AK89 is a StrR mutant of the native strain CIAM1775, a symbiont of Medicago lupulina that adapted to a saline and arid habitat in NW Kazakhstan. CIAM1775 is an effective inoculant of M. lupulina cv. Mira (fodder type standard), cultivated on moderately acid soils in the NW agricultural region of Russia. Strain L6-AK89 makes it possible to obtain the expected high (>150%) increases in dry mass of the same plant variety in plant tests. The L6-AK89 genome has an increased proportion of sequences related to the accessory elements relative to reference strain Rm1021, 7.4% versus 4.8%. A set of 53 nod/noe/nol/nif/fdx/fix genes and 32 genes involved in stress tolerance together with 16S rRNA and recA–atpD–glnII–gyrB–dnaJ were evaluated. The high symbiotic efficiency of L6-АК89 with hop clover is most likely due to unique features of its genome, in combination with structural differences in its nod and stress-related genes, as well as unique clusters of quorum-sensing genes and osmoprotector synthesis.
