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| Author(s): |
Laura Pavan Ióca
Total Authors: 1
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| Document type: | Doctoral Thesis |
| Press: | São Carlos. |
| Institution: | Universidade de São Paulo (USP). Instituto de Química de São Carlos (IQSC/BT) |
| Defense date: | 2020-12-16 |
| Examining board members: |
Roberto Gomes de Souza Berlinck;
Alessandra da Silva Eustaquio;
Lívia Soman de Medeiros;
Monica Tallarico Pupo
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| Advisor: | Roberto Gomes de Souza Berlinck |
| Abstract | |
The present study investigated the metabolites involved on Pseudovibrio brasiliensis Ab134 motility, a marine alpha-Proteobacteria, by using genome sequencing data, gene inactivation experiments and laboratory cultivation techniques. Bioinformatics analyzes allowed the identification of a mixed biosynthetic gene cluster of non-ribosomal peptide syntethases and polyketide synthase conserved in Pseudovibrio and Pseudomonas strains. Gene knock-out in P. brasiliensis Ab134 led the discovery of the compounds encoded by this cluster gene, the heptapeptides pseudovibriamide A1-6 and the depsipeptides pseudovibriamides B1-6. These compounds have a ureido-linkage instead of a peptide bond connecting the first two amino acid residues. Other modifications include a dehydroaminobutyric acid residue, and a thiazole heterocycle. Motility bioassays have shown that the pppA mutant, which does not produce any of the compounds, has reduced swarm motility and increased biofilm formation. The pppD mutants, which produce only pseudovibriamides A, maintained their swarm phenotype, but biofilm formation was impaired. These experiments suggest that the peptides produced by P. brasiliensis Ab134 can influence on phenotypes related to the colonization of the eukaryotic host, the marine sponge Arenosclera brasiliensis. (AU) | |
| FAPESP's process: | 16/05133-7 - Study of marine-derived microrganisms metabolism: chemical profile and biosynthesis |
| Grantee: | Laura Pavan Ióca |
| Support Opportunities: | Scholarships in Brazil - Doctorate |