Banca de QUALIFICAÇÃO: JONATHAS DIEGO LIMA SANTOS

Uma banca de QUALIFICAÇÃO de DOUTORADO foi cadastrada pelo programa.
DISCENTE : JONATHAS DIEGO LIMA SANTOS
DATA : 23/10/2017
HORA: 14:00
LOCAL: Sala de Reuniões do CB
TÍTULO:

PROTEOMIC ANALYSIS OF CHROMOBACTERIUM VIOLACEUM SUBMITTED TO SIMULATED MICROGRAVITY

PALAVRAS-CHAVES:

Proteomics, C. violaceum, simulated microgravity

PÁGINAS: 92
GRANDE ÁREA: Ciências Biológicas
ÁREA: Bioquímica
RESUMO:

 

Chromobcterium violaceum is a Gram-negative bacteria, which has been found at tropical and subtropical regions. Some proteomic studies performed with this bacterium have demonstrated its ability to adapt to environmental challenges such as high iron concentration and oxidative stress exposure. However, no study was made with this specie submitted to simulated microgravity (SMG). SMG refers to conditions in which the gravity is artificially reduced to less than 1 G. Life on Earth has evolved at 1g and study SMG is important to understand the overall changes that organisms might face in space travels. Therefore, the aim of this study was to characterize the response of C. violaceum, as free-living model organism, cultured at SMG, using proteomics techniques in order to understand how this bacterium response to this stress. SMG was achieved by rotating in a horizontal direction parallel to the gravitational vector on the rotating cell culture systems. SMG was conducted at a speed of 40 rpm for a period of 24 hours to obtain the growth curve every 2 hours. Total protein extraction was made in two times: 5 and 12 hours, corresponding to early (MG5) and late (MG12) exponential phase, respectively. After trypsinization, samples were analyzed with Q-TOF mass spectrometer. In our results, we detected 155 proteins during MG5, from which 18 proteins were upregulated, 19 down-regulated and 17 proteins were exclusive when compared to GN5. In MG12 were identified 173 proteins, from which 17 were upregulated, 22 down-regulated and 28 exclusive when compared to control. When comparing the amount of proteins identified in both early (5 hours) and late (12 hours) exponential phase, we detected 212 proteins during MG5 and 193 during MG12 from which 145 of them are common to both phases. We also observed a decrease of Chromobacterium violaceum growth at SMG when compared to bacterial cultures submitted to normal gravity. Proteins correlated with transcriptional processes and release of energy through aerobic pathways were down-regulated, while proteins involved with the inhibition of transcription, anaerobic pathway and cell survival had their expression increased, indicating a decrease in metabolism and proliferation of C. violaceum. SMG can cause alterations in respiratory metabolism, decreasing of transcription and translation rates and, consequently, Chromobacterium violaceum proliferation. These data can be understood as a strategy for maintenance and survival at reduced gravity environment.

 

 

MEMBROS DA BANCA:
Interno - 1549705 - ADRIANA FERREIRA UCHOA
Externo à Instituição - DANIEL CHAVES DE LIMA - IFRN
Presidente - 1453487 - KATIA CASTANHO SCORTECCI