Naslov
Genetic methods for the manipulation of polyketide-producing actinomycetes

Autori
Cullum, John ; Hranueli, Daslav ; Lal, Rup ; Padilla, Gabriel

Vrsta, podvrsta i kategorija rada
Sažeci sa skupova, sažetak, znanstveni

Izvornik
Program and Abstracts / Kniewald, Zlatko et al. - Zagreb : Hrvatsko Društvo za Biotehnologiju, 2001, 21 (IL-13)

Skup
Biotechnology and Environment Scientific Conference with International Participation

Mjesto i datum
Zagreb, Hrvatska, 19.02.2001. - 21.02.2001

Vrsta sudjelovanja
Pozvano predavanje

Vrsta recenzije
Međunarodna recenzija

Ključne riječi
Polyketides; actinomycetes; biosynthetic clusters; genetic manipulation

Sažetak
Polyketides produced by actinomycetes are of great industrial importance (e.g. avermectin from Streptomyces avermitilis, oxytetracycline from Streptomyces rimosus, rifamycin from Amycolatopsis mediterranei). Some polyketide synthetases are of the Type I modular form (e.g. avermectin, rifamycin) in which each extension step is mediated by its own module. In Type II polyketide synthetases (e.g. oxytetracycline) the enzyme is used iteratively. In both cases, genetic manipulation of the biosynthetic clusters can produce novel polyketides. Because of the large size of the clusters (typically 30-150 kb) this is usually achieved by introducing constructs made by in vitro genetics into the clusters by homologous recombination. Many industrially important strains give problems for genetic manipulation including low transformation frequencies, the possession of methylation-dependent restriction systems, the failure of common cloning vectors to replicate in the strain, resistance to antibiotics commonly used in cloning vectors and the occurrence of genetic instability. Instead of protoplast transformation it is possible to use electroporation or conjugation from E. coli to introduce DNA into some species. One strategy to select the required recombination events is the use of counterselectable markers and linear plasmid vectors should be useful in future.

Izvorni jezik
Engleski

Znanstvena područja
Prehrambena tehnologija

POVEZANOST RADA