@article{fdi:010071014,
  title = {{T}he very long chain fatty acid ({C}-26:25{OH}) linked to the lipid a is important for the fitness of the photosynthetic {B}radyrhizobium strain {ORS}278 and the establishment of a successful symbiosis with {A}eschynomene legumes},
  author = {{B}usset, {N}. and {D}i {L}orenzo, {F}. and {P}almigiano, {A}. and {S}turiale, {L}. and {G}ressent, {F}. and {F}ardoux, {J}o{\¨e}l and {G}ully, {D}jamel and {C}haintreuil, {C}l{\'e}mence and {M}olinaro, {A}. and {S}ilipo, {A}. and {G}iraud, {E}ric},
  editor = {},
  language = {{ENG}},
  abstract = {{I}n rhizobium strains, the lipid {A} is modified by the addition of a very long-chain fatty acid ({VLCFA}) shown to play an important role in rigidification of the outer membrane, thereby facilitating their dual life cycle, outside and inside the plant. {I}n {B}radyrhizobium strains, the lipid {A} is more complex with the presence of at least two {VLCFA}s, one covalently linked to a hopanoid molecule, but the importance of these modifications is not well-understood. {I}n this study, we identified a cluster of {VLCFA} genes in the photosynthetic {B}radyrhizobium strain {ORS}278, which nodulates {A}eschynomene plants in a {N}od factor-independent process. {W}e tried to mutate the different genes of the {VLCFA} gene cluster to prevent the synthesis of the {VLCFA}s, but only one mutant in the lpx{XL} gene encoding an acyltransferase was obtained. {S}tructural analysis of the lipid {A} showed that {L}px{XL} is involved in the transfer of the {C}-26:25{OH} {VLCFA} to the lipid {A} but not in the one of the {C}30:29{OH} {VLCFA} which harbors the hopanoid molecule. {D}espite maintaining the second {VLCFA}, the ability of the mutant to cope with various stresses (low p{H}, high temperature, high osmolarity, and antimicrobial peptides) and to establish an efficient nitrogen-fixing symbiosis was drastically reduced. {I}n parallel, we investigated whether the {BRADO}0045 gene, which encodes a putative acyltransferase displaying a weak identity with the apo-lipoprotein {N}-acyltransferase {L}nt, could be involved in the transfer of the {C}-30:29{OH} {VLCFA} to the lipid {A}. {A}lthough the mutant exhibited phenotypes similar to the lpx{XL} mutant, no difference in the lipid {A} structure was observed from that in the wild-type strain, indicating that this gene is not involved in the modification of lipid {A}. {O}ur results advance our knowledge of the biosynthesis pathway and the role of {VLCFA}s-modified lipid {A} in free-living and symbiotic states of {B}radyrhizobium strains.},
  keywords = {{VLCFA} ; lipid {A} ; {B}radyrhizobium ; acyltransferase ; symbiosis ; {A}eschynomene},
  booktitle = {},
  journal = {{F}rontiers in {M}icrobiology},
  volume = {8},
  numero = {},
  pages = {art. 1821 [13 p.]},
  ISSN = {1664-302{X}},
  year = {2017},
  DOI = {10.3389/fmicb.2017.01821},
  URL = {https://www.documentation.ird.fr/hor/fdi:010071014},
}