| Autor: |
Warshan D; Department of Ecology, Environment and Plant Sciences, Stockholm University, Stockholm, Sweden., Espinoza JL; J Craig Venter Institute, La Jolla, CA, USA., Stuart RK; Physical and Life Sciences Directorate, Lawrence Livermore National Laboratory, Livermore, CA, USA., Richter RA; J Craig Venter Institute, La Jolla, CA, USA., Kim SY; Department of Ecology, Environment and Plant Sciences, Stockholm University, Stockholm, Sweden., Shapiro N; US Department of Energy Joint Genome Institute, Walnut Creek, CA, USA., Woyke T; US Department of Energy Joint Genome Institute, Walnut Creek, CA, USA., C Kyrpides N; US Department of Energy Joint Genome Institute, Walnut Creek, CA, USA., Barry K; US Department of Energy Joint Genome Institute, Walnut Creek, CA, USA., Singan V; US Department of Energy Joint Genome Institute, Walnut Creek, CA, USA., Lindquist E; US Department of Energy Joint Genome Institute, Walnut Creek, CA, USA., Ansong C; Biological Sciences Division, Pacific Northwest National Laboratory, Richland, WA, USA., Purvine SO; Environmental Molecular Sciences Laboratory, Pacific Northwest National Laboratory, Richland, WA, USA., M Brewer H; Environmental Molecular Sciences Laboratory, Pacific Northwest National Laboratory, Richland, WA, USA., Weyman PD; J Craig Venter Institute, La Jolla, CA, USA., Dupont CL; J Craig Venter Institute, La Jolla, CA, USA., Rasmussen U; Department of Ecology, Environment and Plant Sciences, Stockholm University, Stockholm, Sweden. |
| Abstrakt: |
Dinitrogen (N 2 )-fixation by cyanobacteria in symbiosis with feathermosses is the primary pathway of biological nitrogen (N) input into boreal forests. Despite its significance, little is known about the cyanobacterial gene repertoire and regulatory rewiring needed for the establishment and maintenance of the symbiosis. To determine gene acquisitions and regulatory changes allowing cyanobacteria to form and maintain this symbiosis, we compared genomically closely related symbiotic-competent and -incompetent Nostoc strains using a proteogenomics approach and an experimental set up allowing for controlled chemical and physical contact between partners. Thirty-two gene families were found only in the genomes of symbiotic strains, including some never before associated with cyanobacterial symbiosis. We identified conserved orthologs that were differentially expressed in symbiotic strains, including protein families involved in chemotaxis and motility, NO regulation, sulfate/phosphate transport, and glycosyl-modifying and oxidative stress-mediating exoenzymes. The physical moss-cyanobacteria epiphytic symbiosis is distinct from other cyanobacteria-plant symbioses, with Nostoc retaining motility, and lacking modulation of N 2 -fixation, photosynthesis, GS-GOGAT cycle and heterocyst formation. The results expand our knowledge base of plant-cyanobacterial symbioses, provide a model of information and material exchange in this ecologically significant symbiosis, and suggest new currencies, namely nitric oxide and aliphatic sulfonates, may be involved in establishing and maintaining the cyanobacteria-feathermoss symbiosis. |
Full text from SpringerLink