Involvement of g proteins and camp in the production of chitinolytic enzymes by Trichoderma harzianum
Braz. j. microbiol
;
33(2): 169-173, Apr.-Jun. 2002. ilus
Artigo
em Inglês
| LILACS
| ID: lil-330266
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), N6¾2'-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(per cent), 77(per cent) and 37(per cent), respectively. AlCl3/KF (100 µM/10 mM and 200 µM/ 20 mM) decreased the activity by 85(per cent)and 95(per cent), respectively. Cholera (10 µ/mL) and pertussis (20 µ/mL) toxins also affected NAGase activity, causing a decrease of approximately 75(per cent). 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.
Texto completo:
DisponíveL
Índice:
LILACS (Américas)
Assunto principal:
Trichoderma
/
Técnicas In Vitro
/
Quitinases
/
Proteínas de Ligação ao GTP
/
Enzimas
Idioma:
Inglês
Revista:
Braz. j. microbiol
Assunto da revista:
Microbiologia
Ano de publicação:
2002
Tipo de documento:
Artigo
País de afiliação:
Brasil
Instituição/País de afiliação:
Universidade Federal de Goiás/BR
/
Universidade de Brasilia/BR
/
Universidade de Brasília/BR
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