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. 1995 May;177(10):2781–2788. doi: 10.1128/jb.177.10.2781-2788.1995

Use of reporter genes to identify recessive trans-acting mutations specifically involved in the regulation of Aspergillus nidulans penicillin biosynthesis genes.

A A Brakhage 1, J Van den Brulle 1
PMCID: PMC176949  PMID: 7677843

Abstract

Starting from three amino acid precursors, penicillin biosynthesis is catalyzed by three enzymes which are encoded by the following three genes: acvA (pcbAB), ipnA (pcbC), and aat (penDE). To identify trans-acting mutations which are specifically involved in the regulation of these secondary metabolism genes, a molecular approach was employed by using an Aspergillus nidulans strain (AXTII9) carrying acvA-uidA and ipnA-lacZ gene fusions integrated in double copies at the chromosomal argB gene. On minimal agar plates supplemented with X-Gal (5-bromo-4-chloro-3-indolyl-beta-D-galactopyranoside), colonies of such a strain stained blue, which is indicative of ipnA-lacZ expression. After mutagenesis with UV light, colonies were isolated on agar plates with lactose as the carbon source, which produced only a faint blue color or no color at all. Such mutants (named Prg for penicillin regulation) most likely were defective in trans-acting genes. Control experiments revealed that the mutants studied still carried the correct number of gene fusions. In a fermentation run, mutants Prg-1 and Prg-6 exhibited only 20 to 50% of the ipnA-lacZ expression of the wild-type strain and produced only 20 to 30% of the penicillin produced by the wild-type strain. Western blot (immunoblot) analysis showed that these mutants contained reduced amounts of ipnA gene product, i.e., isopenicillin N synthase. Both mutant Prg-1 and mutant Prg-6 also differed in acvA-uidA expression levels from the wild type. Segregation analysis indicated that for both mutants the Prg phenotype resulted from mutation of a single gene. Two different complementation groups, which were designated prgA1 and prgB1, were identified. However, the specific activity of the aat (penDE) gene product, i.e., acyl coenzyme A:6-aminopenicillanic acid acyltransferase, was essentially the same for the mutants as for the wild-type strain, implying that the last step of the penicillin biosynthetic pathway is not affected by the trans-acting mutations identified.

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Selected References

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  1. Aharonowitz Y., Cohen G., Martin J. F. Penicillin and cephalosporin biosynthetic genes: structure, organization, regulation, and evolution. Annu Rev Microbiol. 1992;46:461–495. doi: 10.1146/annurev.mi.46.100192.002333. [DOI] [PubMed] [Google Scholar]
  2. Bailey C., Arst H. N., Jr Carbon catabolite repression in Aspergillos nidulans. Eur J Biochem. 1975 Feb 21;51(2):573–577. doi: 10.1111/j.1432-1033.1975.tb03958.x. [DOI] [PubMed] [Google Scholar]
  3. Bradford M. M. A rapid and sensitive method for the quantitation of microgram quantities of protein utilizing the principle of protein-dye binding. Anal Biochem. 1976 May 7;72:248–254. doi: 10.1006/abio.1976.9999. [DOI] [PubMed] [Google Scholar]
  4. Brakhage A. A., Browne P., Turner G. Analysis of the regulation of penicillin biosynthesis in Aspergillus nidulans by targeted disruption of the acvA gene. Mol Gen Genet. 1994 Jan;242(1):57–64. doi: 10.1007/BF00277348. [DOI] [PubMed] [Google Scholar]
  5. Brakhage A. A., Browne P., Turner G. Regulation of Aspergillus nidulans penicillin biosynthesis and penicillin biosynthesis genes acvA and ipnA by glucose. J Bacteriol. 1992 Jun;174(11):3789–3799. doi: 10.1128/jb.174.11.3789-3799.1992. [DOI] [PMC free article] [PubMed] [Google Scholar]
  6. Brakhage A. A., Putzer H., Shazand K., Röschenthaler R. J., Grunberg-Manago M. Bacillus subtilis phenylalanyl-tRNA synthetase genes: cloning and expression in Escherichia coli and B. subtilis. J Bacteriol. 1989 Feb;171(2):1228–1232. doi: 10.1128/jb.171.2.1228-1232.1989. [DOI] [PMC free article] [PubMed] [Google Scholar]
  7. Brakhage A. A., Turner G. L-lysine repression of penicillin biosynthesis and the expression of penicillin biosynthesis genes acvA and ipnA in Aspergillus nidulans. FEMS Microbiol Lett. 1992 Nov 1;77(1-3):123–127. doi: 10.1016/0378-1097(92)90142-b. [DOI] [PubMed] [Google Scholar]
  8. Caddick M. X., Brownlee A. G., Arst H. N., Jr Regulation of gene expression by pH of the growth medium in Aspergillus nidulans. Mol Gen Genet. 1986 May;203(2):346–353. doi: 10.1007/BF00333978. [DOI] [PubMed] [Google Scholar]
  9. DORN G. GENETIC ANALYSIS OF THE PHOSPHATASES IN ASPERGILLUS NIDULANS. Genet Res. 1965 Feb;6:13–26. doi: 10.1017/s0016672300003943. [DOI] [PubMed] [Google Scholar]
  10. Davis M. A., Hynes M. J. Regulatory genes in Aspergillus nidulans. Trends Genet. 1989 Jan;5(1):14–19. doi: 10.1016/0168-9525(89)90006-1. [DOI] [PubMed] [Google Scholar]
  11. Esmahan C., Alvarez E., Montenegro E., Martin J. F. Catabolism of lysine in Penicillium chrysogenum leads to formation of 2-aminoadipic acid, a precursor of penicillin biosynthesis. Appl Environ Microbiol. 1994 Jun;60(6):1705–1710. doi: 10.1128/aem.60.6.1705-1710.1994. [DOI] [PMC free article] [PubMed] [Google Scholar]
  12. Espeso E. A., Peñalva M. A. Carbon catabolite repression can account for the temporal pattern of expression of a penicillin biosynthetic gene in Aspergillus nidulans. Mol Microbiol. 1992 Jun;6(11):1457–1465. doi: 10.1111/j.1365-2958.1992.tb00866.x. [DOI] [PubMed] [Google Scholar]
  13. Espeso E. A., Tilburn J., Arst H. N., Jr, Peñalva M. A. pH regulation is a major determinant in expression of a fungal penicillin biosynthetic gene. EMBO J. 1993 Oct;12(10):3947–3956. doi: 10.1002/j.1460-2075.1993.tb06072.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
  14. Fantes P. A., Roberts C. F. Beta-galactosidase activity and lactose utilization in Aspergillus nidulans. J Gen Microbiol. 1973 Aug;77(2):417–486. doi: 10.1099/00221287-77-2-417. [DOI] [PubMed] [Google Scholar]
  15. Feinberg A. P., Vogelstein B. A technique for radiolabeling DNA restriction endonuclease fragments to high specific activity. Anal Biochem. 1983 Jul 1;132(1):6–13. doi: 10.1016/0003-2697(83)90418-9. [DOI] [PubMed] [Google Scholar]
  16. Johnstone I. L., Hughes S. G., Clutterbuck A. J. Cloning an Aspergillus nidulans developmental gene by transformation. EMBO J. 1985 May;4(5):1307–1311. doi: 10.1002/j.1460-2075.1985.tb03777.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
  17. Kalman L. V., Gunsalus R. P. The frdR gene of Escherichia coli globally regulates several operons involved in anaerobic growth in response to nitrate. J Bacteriol. 1988 Feb;170(2):623–629. doi: 10.1128/jb.170.2.623-629.1988. [DOI] [PMC free article] [PubMed] [Google Scholar]
  18. Kolar M., Punt P. J., van den Hondel C. A., Schwab H. Transformation of Penicillium chrysogenum using dominant selection markers and expression of an Escherichia coli lacZ fusion gene. Gene. 1988;62(1):127–134. doi: 10.1016/0378-1119(88)90586-0. [DOI] [PubMed] [Google Scholar]
  19. Laemmli U. K. Cleavage of structural proteins during the assembly of the head of bacteriophage T4. Nature. 1970 Aug 15;227(5259):680–685. doi: 10.1038/227680a0. [DOI] [PubMed] [Google Scholar]
  20. MacCabe A. P., Riach M. B., Unkles S. E., Kinghorn J. R. The Aspergillus nidulans npeA locus consists of three contiguous genes required for penicillin biosynthesis. EMBO J. 1990 Jan;9(1):279–287. doi: 10.1002/j.1460-2075.1990.tb08106.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
  21. Macdonald K. D., Holt G. Genetics of biosynthesis and overproduction of penicillin. Sci Prog. 1976 Winter;63(252):547–573. [PubMed] [Google Scholar]
  22. Menne S., Walz M., Kück U. Expression studies with the bidirectional pcbAB-pcbC promoter region from Acremonium chrysogenum using reporter gene fusions. Appl Microbiol Biotechnol. 1994 Oct;42(1):57–66. doi: 10.1007/BF00170225. [DOI] [PubMed] [Google Scholar]
  23. Miller J. R., Ingolia T. D. Cloning and characterization of beta-lactam biosynthetic genes. Mol Microbiol. 1989 May;3(5):689–695. doi: 10.1111/j.1365-2958.1989.tb00217.x. [DOI] [PubMed] [Google Scholar]
  24. PONTECORVO G., ROPER J. A., HEMMONS L. M., MACDONALD K. D., BUFTON A. W. J. The genetics of Aspergillus nidulans. Adv Genet. 1953;5:141–238. doi: 10.1016/s0065-2660(08)60408-3. [DOI] [PubMed] [Google Scholar]
  25. Queener S. W. Molecular biology of penicillin and cephalosporin biosynthesis. Antimicrob Agents Chemother. 1990 Jun;34(6):943–948. doi: 10.1128/aac.34.6.943. [DOI] [PMC free article] [PubMed] [Google Scholar]
  26. Rabin R. S., Stewart V. Either of two functionally redundant sensor proteins, NarX and NarQ, is sufficient for nitrate regulation in Escherichia coli K-12. Proc Natl Acad Sci U S A. 1992 Sep 15;89(18):8419–8423. doi: 10.1073/pnas.89.18.8419. [DOI] [PMC free article] [PubMed] [Google Scholar]
  27. Rowlands R. T., Turner G. Nuclear and extranuclear inheritance of oligomycin resistance in Aspergillus nidulans. Mol Gen Genet. 1973 Nov 12;126(3):201–216. doi: 10.1007/BF00267531. [DOI] [PubMed] [Google Scholar]
  28. Shah A. J., Tilburn J., Adlard M. W., Arst H. N., Jr pH regulation of penicillin production in Aspergillus nidulans. FEMS Microbiol Lett. 1991 Jan 15;61(2-3):209–212. doi: 10.1016/0378-1097(91)90553-m. [DOI] [PubMed] [Google Scholar]
  29. Timberlake W. E., Marshall M. A. Genetic regulation of development in Aspergillus nidulans. Trends Genet. 1988 Jun;4(6):162–169. doi: 10.1016/0168-9525(88)90022-4. [DOI] [PubMed] [Google Scholar]
  30. Towbin H., Staehelin T., Gordon J. Electrophoretic transfer of proteins from polyacrylamide gels to nitrocellulose sheets: procedure and some applications. Proc Natl Acad Sci U S A. 1979 Sep;76(9):4350–4354. doi: 10.1073/pnas.76.9.4350. [DOI] [PMC free article] [PubMed] [Google Scholar]
  31. Vining L. C. Secondary metabolism, inventive evolution and biochemical diversity--a review. Gene. 1992 Jun 15;115(1-2):135–140. doi: 10.1016/0378-1119(92)90551-y. [DOI] [PubMed] [Google Scholar]
  32. Woloshuk C. P., Foutz K. R., Brewer J. F., Bhatnagar D., Cleveland T. E., Payne G. A. Molecular characterization of aflR, a regulatory locus for aflatoxin biosynthesis. Appl Environ Microbiol. 1994 Jul;60(7):2408–2414. doi: 10.1128/aem.60.7.2408-2414.1994. [DOI] [PMC free article] [PubMed] [Google Scholar]
  33. van Gorcom R. F., Punt P. J., Pouwels P. H., van den Hondel C. A. A system for the analysis of expression signals in Aspergillus. Gene. 1986;48(2-3):211–217. doi: 10.1016/0378-1119(86)90079-x. [DOI] [PubMed] [Google Scholar]

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