Plasmid gene AZOBR_p60126 impacts biosynthesis of lipopolysaccharide II and swarming motility in Azospirillum brasilense Sp245.
J Basic Microbiol
; 60(7): 613-623, 2020 Jul.
Article
in En
| MEDLINE
| ID: mdl-32378235
ABSTRACT
The facultative plant endophyte Azospirillum brasilense Sp245 synthesizes two high-molecular-weight lipopolysaccharides, LPSI and LPSII, which comprise identical d-rhamnan O-polysaccharides and, presumably different core oligosaccharides. Previously, using random insertion mutagenesis, we constructed the LpsII- mutant KM139 of strain Sp245 that possessed an Omegon-Km insertion in plasmid AZOBR_p6. Here, we found that in KM139, Omegon-Km disrupted the coding sequence AZOBR_p60126 for a putative glycosyltransferase related to mannosyltransferases and rhamnosyltransferases. To verify its function, we cloned the AZOBR_p60126 gene of strain Sp245 in the expression vector plasmid pRK415 and transferred the construct pRK415-p60126 into KM139. In the complemented mutant KM139 (pRK415-p60126), the wild-type LPSI+ LPSII+ profile was recovered. We also compared the swimming and swarming motilities of strains Sp245, Sp245 (pRK415), KM139, KM139 (pRK415), and KM139 (pRK415-p60126). All these strains had the same flagellar-dependent swimming speeds, but on soft media, the LpsI+ LpsII- strains KM139 and KM139 (pRK415) swarmed significantly faster than the other LpsI+ LpsII+ strains. Such interstrain differences in swarming motility were more pronounced on 0.4% than on 0.5% soft agar plates. These data show that the AZOBR_p60126-encoded putative glycosyltransferase significantly affects the lipopolysaccharide profile and, as a consequence, the social motility of azospirilla.
Key words
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Azospirillum brasilense
/
Lipopolysaccharides
/
Glycosyltransferases
/
Locomotion
Country/Region as subject:
America do sul
/
Brasil
Language:
En
Journal:
J Basic Microbiol
Journal subject:
MICROBIOLOGIA
Year:
2020
Document type:
Article
Affiliation country:
RUSSIA