| Autor: |
Taboada H; 1Programa de Genómica Funcional de Procariotes, Centro de Ciencias Genómicas, Universidad Nacional Autónoma de México, Cuernavaca, Morelos C. P. 62210, México., Meneses N; 1Programa de Genómica Funcional de Procariotes, Centro de Ciencias Genómicas, Universidad Nacional Autónoma de México, Cuernavaca, Morelos C. P. 62210, México.; 3Faculty of Science, Department of Chemistry and Biochemistry, University of Bern, 3010 Bern, Switzerland.; 2Mass Spectrometry and Proteomics Laboratory, Department of Clinical Research, University of Bern, 3010 Bern, Switzerland., Dunn MF; 1Programa de Genómica Funcional de Procariotes, Centro de Ciencias Genómicas, Universidad Nacional Autónoma de México, Cuernavaca, Morelos C. P. 62210, México., Vargas-Lagunas C; 1Programa de Genómica Funcional de Procariotes, Centro de Ciencias Genómicas, Universidad Nacional Autónoma de México, Cuernavaca, Morelos C. P. 62210, México., Buchs N; 2Mass Spectrometry and Proteomics Laboratory, Department of Clinical Research, University of Bern, 3010 Bern, Switzerland., Castro-Mondragón JA; 4Aix Marseille University, INSERM, TAGC, Theory and Approaches of Genomic Complexity, UMR_S 1090, Marseille, France., Heller M; 2Mass Spectrometry and Proteomics Laboratory, Department of Clinical Research, University of Bern, 3010 Bern, Switzerland., Encarnación S; 1Programa de Genómica Funcional de Procariotes, Centro de Ciencias Genómicas, Universidad Nacional Autónoma de México, Cuernavaca, Morelos C. P. 62210, México. |
| Abstrakt: |
Rhizobium etli CE3 grown in succinate-ammonium minimal medium (MM) excreted outer membrane vesicles (OMVs) with diameters of 40 to 100 nm. Proteins from the OMVs and the periplasmic space were isolated from 6 and 24 h cultures and identified by proteome analysis. A total of 770 proteins were identified: 73.8 and 21.3 % of these occurred only in the periplasm and OMVs, respectively, and only 4.9 % were found in both locations. The majority of proteins found in either location were present only at 6 or 24 h: in the periplasm and OMVs, only 24 and 9 % of proteins, respectively, were present at both sampling times, indicating a time-dependent differential sorting of proteins into the two compartments. The OMVs contained proteins with physiologically varied roles, including Rhizobium adhering proteins (Rap), polysaccharidases, polysaccharide export proteins, auto-aggregation and adherence proteins, glycosyl transferases, peptidoglycan binding and cross-linking enzymes, potential cell wall-modifying enzymes, porins, multidrug efflux RND family proteins, ABC transporter proteins and heat shock proteins. As expected, proteins with known periplasmic localizations (phosphatases, phosphodiesterases, pyrophosphatases) were found only in the periplasm, along with numerous proteins involved in amino acid and carbohydrate metabolism and transport. Nearly one-quarter of the proteins present in the OMVs were also found in our previous analysis of the R. etli total exproteome of MM-grown cells, indicating that these nanoparticles are an important mechanism for protein excretion in this species. |
