Data/hora: 09/06/2024 11:58:16

Provedor de dados: | Brazilian Journal of Microbiology
País: | Brazil
Título: | Involvement of G proteins and cAMP in the production of chitinolytic enzymes by Trichoderma harzianum
Autores: | Firmino,Alexandre A.P.; Ulhoa,Cirano J.; Sousa,Marcelo V.; Ferreira Filho,Edivaldo X.; Ricart,Carlos A.O.
Data: | 2002-06-01
Ano: | 2002
Palavras-chave: | Trichoderma; N-acetylglucosaminidase; Chitinase; CAMP; G protein.
Resumo: | The effect of G protein modulators and cyclic AMP (cAMP) on N-acetylglucosaminidase (NAGase) production was investigated during 84 h of growth of a Trichoderma harzianum strain in chitin-containing medium. Caffeine (5 mM), N6--2'-O-dibutyryladenosine 3'5'-cyclic monophosphate sodium salt (dBcAMP) (1 mM) and 3-isobutyl-1-methylxanthine (IBMX) (2 mM) decreased extracellular NAGase activity by 80%, 77% and 37%, respectively. AlCl3/KF (100 µM/10 mM and 200 µM/ 20 mM) decreased the activity by 85% and 95%, respectively. Cholera (10 µ/mL) and pertussis (20 µ/mL) toxins also affected NAGase activity, causing a decrease of approximately 75%. Upon all treatments, protein bands of approximately 73 kDa, 68 kDa and 45 kDa had their signals diminished whilst a 50 kDa band was enhanced only by treatment with cholera and pertussis toxins. N-terminal sequencing analysis identified the 73 kDa and 68 kDa proteins as being T. harzianum NAGase in two different truncated forms whereas the 45 kDa band comprised a T. harzianum endochitinase. The 50 kDa protein showed sequence similarity to Coriolus vesicolor cellobiohydrolase. The above results suggest that a signaling pathway comprising G-proteins, adenylate cyclase and cAMP may be involved in the synthesis of T. harzianum chitinases.
Tipo: | Info:eu-repo/semantics/article
Idioma: | Inglês
Identificador: | http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1517-83822002000200015
Editor: | Sociedade Brasileira de Microbiologia
Relação: | 10.1590/S1517-83822002000200015
Formato: | text/html
Fonte: | Brazilian Journal of Microbiology  v.33 n.2 2002
Fonte: | info:eu-repo/semantics/openAccess