Isolation of Auxotrophs of Penicillium chrysogenum and their Penicillin Yields

Macdonald, K. D.; Hutchinson, J. M.; Gillett, W. A.

doi:10.1099/00221287-33-3-365

Cited by 62 publications

(16 citation statements)

References 11 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…The media for routine growth, conidial production and plating of conidia following mutagenesis and the procedures for sampling and genotype testing of survivors and storage of cultures were all as previously described (Simpson & Caten, 1979). The media for penicillin fermentation and biological assay were those described by Macdonald et al (1963) and by Merrick & Caten (1975a, b), respectively. To compensate for a pleiotropic effect of the pabaAl mutation on penicillin titre, the fermentation medium was supplemented withp-aminobenzoic acid to 2 pg ml-l. With the exception of the penicillin fermentations, which were carried out at 25 "C, all incubation was at 35 "C.…”

Section: E T H O D Smentioning

confidence: 99%

Recurrent Mutation and Selection for Increased Penicillin Titre in Aspergillus nidulans

Simpson

Caten

1979

Journal of General Microbiology

View full text Add to dashboard Cite

Recurrent mutation and selection has been used to increase penicillin titre in two closely related strains of Aspergillus nidulans. A selection programme was initiated from each of the two strains (programmes A and B) and continued through six cycles of mutation and selection. Near-ultraviolet light in conjuction with 8-methoxypsoralen was employed as the sole mutagen throughout programme A and ethyl methanesulphonate as the sole mutagen throughout programme B. Excluding the first cycle of A, where only 50 strains were assayed, the selection programmes were identical. In each programme, 100 survivors were assayed for penicillin titre after each mutagenic treatment and, on the basis of a single yield test, the best five strains were picked and carried forward to the next cycle. In both selection programmes, a near 300 yo increase in penicillin titre was achieved. This yield advance illustrates the effectiveness for strain development of experimental designs involving successive cycles of mutagenesis with a single-stage screen and the selection of the top few percent survivors in each cycle.

show abstract

Section: E T H O D Smentioning

confidence: 99%

Recurrent Mutation and Selection for Increased Penicillin Titre in Aspergillus nidulans

Simpson

Caten

1979

Journal of General Microbiology

View full text Add to dashboard Cite

show abstract

“…Ltd). The fermentation medium for penicillin production was that given by Macdonald, Hutchinson & Gillett (1963). It was dispensed in 40 ml amounts into 250 ml Erlenmeyer flasks which were then plugged with disposable foam bungs and autoclaved for 15 min at IOO kN/m2 (15 lbf/in2).…”

Section: E T H O D Smentioning

confidence: 99%

The Inheritance of Penicillin Titre in Wild-type Isolates of Aspergillus Nidulans

Merrick

Caten

1975

Journal of General Microbiology

View full text Add to dashboard Cite

S U M M A R YIn a sample of 52 wild-type isolates of Aspergillus nidulans, penicillin titre ranged from 0.0 to 14'4 units/ml. These differences in titre were under genetic control. Most of the variation between isolates was attributable to differences between heterokaryon-compatibility groups although significant differences were also found within groups. Genetic variation for penicillin titre was observed among the progeny in four of seven crosses between wild-type isolates. In these four crosses the variation was continuous, indicating that this is a polygenically determined character, and progeny with titres superior and inferior to those of the parents were produced. The genes determining penicillin production are predominantly additive in their action. Crosses between heterokaryon-incompatible isolates generated more genetic variation than those involving compatible parents, supporting the hypothesis that heterokaryon-compatible isolates are frequently closely related.

show abstract

“…In addition, we investigated whether the peptide is excreted in the culture medium and if it is present in a non-penicillin-producing strain. (17) were used to inoculate 50 ml of the sulfur-free medium of Halliday and Arnstein (12). Labeled sulfate was added after 24 h; L-valine and L-a-aminoadipic acid (50 ,umol of each) were added after 36 h. The mycelia were harvested after 60 h.…”

mentioning

confidence: 99%

Presence of δ-( l -α-Aminoadipyl)- l -Cysteinyl- d -Valine in Fermentations of Penicillium chrysogenum

Adriaens

Meesschaert

Wuyts

et al. 1975

Antimicrob Agents Chemother

View full text Add to dashboard Cite

Cultures of Penicillium chrysogenum , growth with [ 35 S]sulfate or labeled amino acids, were examined by ion-exchange chromatography for possible peptidic precursors of penicillin. A sulfur-containing compound, present in both the mycelial extracts and the culture filtrates, was eluted at the location of the synthetic lld -tripeptide δ-( l -α-aminoadipyl)- l -cysteinyl- d -valine. Since this compound was also labeled when the cultures were incubated with dl -[6- 14 C]α-aminoadipic acid, l -[3,3′- 3 H]cystine, or dl -[1- 14 C]valine, its identity with the synthetic lld -tripeptide can be accepted. No δ-( l -α-aminoadipyl)- l -cysteine or lll -tripeptide were detected. The implications of these findings for tripeptide and penicillin biosynthesis are discussed.

show abstract

Isolation of Auxotrophs of Penicillium chrysogenum and their Penicillin Yields

Cited by 62 publications

References 11 publications

Recurrent Mutation and Selection for Increased Penicillin Titre in Aspergillus nidulans

Recurrent Mutation and Selection for Increased Penicillin Titre in Aspergillus nidulans

The Inheritance of Penicillin Titre in Wild-type Isolates of Aspergillus Nidulans

Presence of δ-( l -α-Aminoadipyl)- l -Cysteinyl- d -Valine in Fermentations of Penicillium chrysogenum

Contact Info

Product

Resources

About