Year: 1989
Type: article
Abstract: gene.6-9Among these, the presence of iron has been shown to dramatically decrease ETA production by reducing the levels of ETA mRNA.'-"In contrast, calcium and glycerol in the growth medium enhance ETA production and the evidence suggests that the effect occurs at the transcriptional level.s,' Genetic studies with mutants have shown that several different chromosomal sites are involved in the expression of the ETA gene, suggesting the presence of a multigenic control Recently, Hedstrom et al. l3 reported the cloning of a gene of P. aeruginosa which, when expressed in toxigenic strains of this bacterium, results in a 10-folbincrease of ETA yields.They also showed that high iron concentrations only partially inhibited ETA overproduction.These results led the authors to postulate the existence of a positive regulatory factor for ETA expression similar to the one described for cholera toxin.14915Clearly, more information is needed to fully understand the regulatory mechanisms governing ETA production.Along these lines, based on the existing knowledge of the media components affecting ETA production and using a previously optimized defined medium,' we discuss in this study the development of an improved protocol for the production of ETA from P. aeruginosa.
Source: Biotechnology and Bioengineering
Language: English
Subfield: Immunology
Field: Immunology and Microbiology
Domain: Life Sciences
Open Access status: bronze
Funder: National Institutes of Health
OpenAlex ID: W2019558115