Banca de DEFESA: CAIO JUNIOR BALDUINO COUTINHO RODRIGUES

Uma banca de DEFESA de DOUTORADO foi cadastrada pelo programa.
DISCENTE : CAIO JUNIOR BALDUINO COUTINHO RODRIGUES
DATA : 22/02/2019
HORA: 09:00
LOCAL: Anfiteatro do DPA-Sala 14
TÍTULO:

Arthropodopathogenic fungi in Tick control:
 Enzymatic and proteomic approaches

PALAVRAS-CHAVES:

Metarhizium spp.; Beauveria bassiana; subcultiving; menadione; MudPIT

PÁGINAS: 121
GRANDE ÁREA: Ciências Agrárias
ÁREA: Medicina Veterinária
RESUMO:

Studies using Metarhizium spp. and Beauveria bassiana to control Rhipicephalus microplus have exponentially increased over the last decade. Here, Chapter I reports the subculturing of three Metarhizium isolates in synthetic culture medium (potato-dextrose-agar - PDA) and its effect on enzymatic activity and virulence to R. microplus. For this, samples were collected of the initial culture (beginning) and after the tenth (10th cycle) and twentieth (20th cycle) growth. Apparently being stable, mainly changes in macromorphology, decrease in radial growth and conidia production, as well as reduction of virulence and Pr1, Pr2 and lipase activities, were detected after the 20th cycle. In Chapter II, the effects of a potent oxidizing agent (menadione - MEN) were explored in the development, virulence to R. microplus, enzymatic activity and protein secretion of M. anisopliae sensu stricto (s.str.). With low tolerance to MEN, for all experiments, a subdose (50% LC50) was initially added to the cultures. In solid medium supplemented with MEN (PDA + MEN), significant changes in the macromorphology of colonies, in addition to conidial enzymatic activities were detected. In contrast, surprisingly, significant improvements in the percentage of larval mortality also occurred. In basal medium (BM) plus R. microplus cuticle (BMRm and BMRm + MEN), in 654 identified proteins, 31 were up- and down-regulated, mainly related to antioxidant activity (catalase), pathogenicity (Pr1B, Pr1D and Pr1K), cell repair and morphogenesis. Finally, Chapter III describes the activity and secretion of proteins (secretoma) of Beauveria bassiana s.l. during Rhipicephalus microplus infection versus normal growth conditions. From BM plus R. microplus cuticle and applying a multidimensional protein identification technology, up to 236 proteins were characterized, being 32 proteins identified in both conditions and 50 exclusively in the infection condition. All proteins were related to different aspects such as host adhesion, cuticular penetration, fungal defense and stress. In this context, a higher number of proteins detected with hydrolysis activity, enzymatic class of all cuticle-degrading enzymes, such as lipases and proteases, were identified and validated through enzymatic assays. In summary, subculturing and oxidative stress, as well as the lack of knowledge about the main metabolites produced during B. bassiana infection, still limit the perspectives of biocontrol, especially the success implement and the environmental track of products based on arthropodopathogenic fungi used in tick control.

MEMBROS DA BANCA:
Externo ao Programa - 1681790 - CRISTIANE MARTINS CARDOSO DE SALLES
Externo à Instituição - GISELA LARA DA COSTA - FIOCRUZ
Externo à Instituição - MARIANA GUEDES CAMARGO - UFRRJ
Interno - 2221855 - PATRICIA SILVA GOLO
Externo à Instituição - SIMONE QUINELATO BEZERRA - FIOCRUZ
Presidente - 387922 - VANIA RITA ELIAS PINHEIRO BITTENCOURT