RESUMEN
The mutant Penicillium chrysogenum strain dogR5, derived from strain AS-P-78, does not respond to glucose regulation of penicillin biosynthesis and β-galactosidase, and is partially deficient in D-glucose phosphorilating activity. We have transformed strain dogR5 with the (hexokinase) hxk2 gene from Saccharomyces cerevisiae. Transformants recovered glucose control of penicillin biosynthesis in different degrees, and acquired a hexokinase (fructose phosphorylating) activity absent in strains AS- P-78 and dogR5. Interestingly, they also recovered glucose regulation of β-galactosidase. On the other hand, glucokinase activity was affected in different ways in the transformants; one of which showed a lower activity than the parental dogR5, but normal glucose regulation of penicillin biosynthesis. Our results show that Penicillium chrysogenum AS-P-78 and dogR5 strains lack hexokinase, and suggest that an enzyme with glucokinase activity is involved in glucose regulation of penicillin biosynthesis and β-galactosidase, thus signaling glucose in both primary and secondary metabolism; however, catalytic and signaling activities seem to be independent.
Asunto(s)
Regulación Fúngica de la Expresión Génica/efectos de los fármacos , Glucosa/metabolismo , Hexoquinasa/metabolismo , Penicilinas/biosíntesis , Penicillium chrysogenum/genética , Penicillium chrysogenum/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Hexoquinasa/genética , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Transformación Genética , beta-Galactosidasa/biosíntesisRESUMEN
The conjunctivitis produced by Neisseria gonorrhoeae is the less frequently reported clinical form of gonococcal infection. We aim to phenotypically characterize N. gonorrhoeae isolated from conjunctivae sites. A total of six cases of this disease were notified in the Camagüey province, Cuba. All the strains isolated were penicillin-producing, showed the serogroup WI and exhibited the same antimicrobial susceptibility pattern and plasmid profile (2.6-3.2-24.5). The results contribute to the characterization of N. gonorrhoeae strains circulating in our environment
Asunto(s)
Humanos , Preescolar , Adulto , Conjuntivitis Bacteriana/microbiología , Neisseria gonorrhoeae/aislamiento & purificación , Gonorrea/tratamiento farmacológico , Gonorrea/microbiología , Neisseria gonorrhoeae/efectos de los fármacos , Resistencia a las Penicilinas , Penicilinas/biosíntesis , Penicilinas/farmacología , Penicilinas/uso terapéutico , Tetraciclinas/farmacología , Tetraciclinas/uso terapéutico , Tetraciclina/farmacología , Tetraciclina/uso terapéuticoRESUMEN
O ácido 6-aminopenicilânico foi acilado com o cloreto de p-benziloxibenzoil ou derivados p'-substituídos obtendo-se penicilina contendo, como cadeia lateral, grupo derivado do ácido p-benziloxibenzóico
Asunto(s)
Ácido Penicilánico/metabolismo , Penicilinas/biosíntesis , QuímicaRESUMEN
Fermentaçöes industriais de produçäo de penicilina que apresentam cristais de ácido oxálico sofrem quebra de viscosidade, micélio fragmentado e teores mais baixos de antibiótico. No presente trabalho foi estudado o efeito de ion oxalato adicionado sob a forma de ácido axálico ou oxalato de amônio. Como concentraçöes intermediários de oxalato de amônio (de 0,5 a 2,25 g/l) apresentaram efeito estimulante, foi testada a hipótese de que o íon amônio era o responsável pelo fato, através da adiçäo de sulfato de amônio. Verificou-se que a adiçäo de 0,45 a 0,90 g/l de amônio aumento da ordem de 10% na produçäo do antibiótico nas fases finais do ciclo de produçäo