Production of cellulases and xylanases under catabolic repression conditions from mutant PR-22 of Cellulomonas flavigena
Por:
Rojas-Rejón O.A., Poggi-Varaldo H.M., Ramos-Valdivia A.C., Martínez-Jiménez A., Cristiani-Urbina E., Martinez, MD, Ponce-Noyola T.
Publicada:
1 ene 2011
Resumen:
Derepressed mutant PR-22 was obtained by N-methyl-N'-nitro-N-nitrosoguanidine (MNNG) mutagenic treatment of Cellulomonas flavigena PN-120. This mutant improved its xylanolytic activity from 26.9 to 40 U mg(-1) and cellulolytic activity from 1.9 to 4 U mg(-1); this represented rates almost 2 and 1.5 times higher, respectively, compared to its parent strain growing in sugarcane bagasse. Either glucose or cellobiose was added to cultures of C. flavigena PN-120 and mutant PR-22 induced with sugarcane bagasse in batch culture. The inhibitory effect of glucose on xylanase activity was more noticeable for parent strain PN-120 than for mutant PR-22. When 20 mM glucose was added, the xylanolytic activity decreased 41% compared to the culture grown without glucose in mutant PR-22, whereas in the PN-120 strain the xylanolytic activity decreased by 49% at the same conditions compared to its own control. Addition of 10 and 15 mM of glucose did not adversely affect CMCase activity in PR-22, but gluc
Filiaciones:
Rojas-Rejón O.A.:
Departamento de Biotecnología y Bioingeniería, Centro de Investigación y de Estudios Avanzados, Instituto Politécnico Nacional, Av. IPN 2508, Zacatenco, DF 07300, Mexico
Poggi-Varaldo H.M.:
Departamento de Biotecnología y Bioingeniería, Centro de Investigación y de Estudios Avanzados, Instituto Politécnico Nacional, Av. IPN 2508, Zacatenco, DF 07300, Mexico
Ramos-Valdivia A.C.:
Departamento de Biotecnología y Bioingeniería, Centro de Investigación y de Estudios Avanzados, Instituto Politécnico Nacional, Av. IPN 2508, Zacatenco, DF 07300, Mexico
Martínez-Jiménez A.:
Inst Biotecnol UNAM, Cuernavaca 62210, Morelos, Mexico
Cristiani-Urbina E.:
Escuela Nacional de Ciencias Biológicas Del IPN, Prolongación Carpio y Plan de Ayala, Plutarco Elías Calles, DF 11340, Mexico
Ponce-Noyola T.:
Departamento de Biotecnología y Bioingeniería, Centro de Investigación y de Estudios Avanzados, Instituto Politécnico Nacional, Av. IPN 2508, Zacatenco, DF 07300, Mexico
|