''Rhizobium lentis'' is a

gram-negative bacterium Gram-negative bacteria are bacteria that do not retain the crystal violet stain used in the Gram staining method of bacterial differentiation. They are characterized by their cell envelopes, which are composed of a thin peptidoglycan cell wall ...

which was isolated from

root nodule Root nodules are found on the roots of plants, primarily legumes, that form a symbiosis with nitrogen-fixing bacteria. Under nitrogen-limiting conditions, capable plants form a symbiotic relationship with a host-specific strain of bacteria known a ...

s of lentils in Bangladesh.

Description

''Rhizobium lentis'' are rod-shaped bacteria found in the soil. They require oxygen and do not form spores. ''Rhizobium lentis'' grow well on YEMA medium

agar Agar ( or ), or agar-agar, is a jelly-like substance consisting of polysaccharides obtained from the cell walls of some species of red algae, primarily from ogonori (''Gracilaria'') and "tengusa" (''Gelidiaceae''). As found in nature, agar is ...

, where they form colonies which are circular, convex and creamy white. These bacteria grow at 12–37 °C but can survive at temperatures as low as 4 °C. Strains grow well at pH 5.5 to 8.2. Most of the strains studied are resistant to ampicillin, kanamycin and nalidixic acid. Strains do not tolerate tetracycline and do not show any growth on LB medium. ''Rhizobium lentis'' can utilize α- D lactose, β-methyl-D-glucoside, D-sorbitol, D-mannito, D-arbitol-glycerol, D-fructose-6-phosphate, L-aspartic acid, D-gluconic acid, mucic acid, D-lactic acid methyl ester, L-lactic acid,

L-histidine Histidine (symbol His or H) is an essential amino acid that is used in the biosynthesis of proteins. It contains an α-amino group (which is in the protonated –NH3+ form under biological conditions), a carboxylic acid group (which is in the d ...

, β-hydroxy-D, L-butyric acid, D-malic acid, L-malic acid,

acetic acid Acetic acid , systematically named ethanoic acid , is an acidic, colourless liquid and organic compound with the chemical formula (also written as , , or ). Vinegar is at least 4% acetic acid by volume, making acetic acid the main component ...

and

formic acid Formic acid (), systematically named methanoic acid, is the simplest carboxylic acid, and has the chemical formula HCOOH and structure . It is an important intermediate in chemical synthesis and occurs naturally, most notably in some ants. Es ...

. They are unable to utilize D-maltose, D-trehalose, D-cellobiose,

gentiobiose Gentiobiose is a disaccharide composed of two units of D-glucose joined with a β(1->6) linkage. It is a white crystalline solid that is soluble in water or hot methanol. Gentiobiose is incorporated into the chemical structure of crocin, the che ...

sucrose Sucrose, a disaccharide, is a sugar composed of glucose and fructose subunits. It is produced naturally in plants and is the main constituent of white sugar. It has the molecular formula . For human consumption, sucrose is extracted and refined ...

, D-raffinose, α-D-glucose,

D-turanose Turanose is a reducing disaccharide. The -isomer is naturally occurring. Its systematic name is α--glucopyranosyl-(1→3)-α--fructofuranose. It is an analog of sucrose not metabolized by higher plants, but rather acquired through the action ...

, D-melibose, mannose, galactose, 3-methyle glucose, inosine, D-aspartic acid, glycyl-L-proline, L-alanine, L-arginine, L-serine, pectine, D-saccharic acid, p-hydroxy-phenylacetic acid, methyl pyruvate, citric acid, bromo-succinic acid, acetoacetic acid or

propionic acid Propionic acid (, from the Greek words πρῶτος : ''prōtos'', meaning "first", and πίων : ''píōn'', meaning "fat"; also known as propanoic acid) is a naturally occurring carboxylic acid with chemical formula CH3CH2CO2H. It is a liq ...

. ''R. lentis'' can grow in the presence of the antibiotic compounds lincomycin,

tetrazolium violet The formazans are compounds of the general formula -N=N-C(R')=N-NH-R" formally derivatives of formazan 2NN=CHN=NH unknown in free form. Formazan dyes are artificial chromogenic products obtained by reduction of tetrazolium salts by dehydrogena ...

and

tetrazolium blue The formazans are compounds of the general formula -N=N-C(R')=N-NH-R" formally derivatives of formazan 2NN=CHN=NH unknown in free form. Formazan dyes are artificial chromogenic products obtained by reduction of tetrazolium salts by dehydrogena ...

but not with 1% sodium lactate,

troleandomycin Troleandomycin (TAO for short) is a macrolide antibiotic. It was sold in Italy (branded Triocetin) and Turkey (branded Tekmisin). It is no longer sold in Italy as of 2018. The drug's mode of action is to bind to the ribosome, specifically in ...

, lithium chloride, potassium tellurite or sodium butyrate. The type strain of ''R. lentis'' is BLR27T (= LMG 28441T = DSMZ 29286T).

Applications

Different strains of this species can form nodules and enhance growth of lentil, peas and lathyrus.

Genetics

''Rhizobium lentis'' is genetically very closely related to the related species ''

Rhizobium etli ''Rhizobium etli'' is a Gram-negative root-nodule bacterium Bacteria (; singular: bacterium) are ubiquitous, mostly free-living organisms often consisting of one biological cell. They constitute a large domain of prokaryotic microorgani ...

'' and '' Rhizobum phaseoli''. The

GC-content In molecular biology and genetics, GC-content (or guanine-cytosine content) is the percentage of nitrogenous bases in a DNA or RNA molecule that are either guanine (G) or cytosine (C). This measure indicates the proportion of G and C bases out o ...

of the type strain's DNA is 61.1%. The genome sequence is available from the National Center for Biotechnology Information and the European nucleotide archive.

History

''Rhizobium lentis'' was first described in 2015 after being isolated from root nodules of ''

Lens culinaris The lentil (''Lens culinaris'' or ''Lens esculenta'') is an edible legume. It is an annual plant known for its lens-shaped seeds. It is about tall, and the seeds grow in pods, usually with two seeds in each. As a food crop, the largest pro ...

'' in the Natore district of Bangladesh. It was named "lentis" in reference to ''Lens'', the plant genus from which the bacteria were isolated.

References

External links