摘要
Penicillin is historically important as the first discovered drug against bacterial infections in human. Although the penicillin biosyn- thetic pathway and regulatory mechanism have been well studied in Penicillium chrysogenum, the compartmentation and molecular transport of penicillin or its precursors are still poorly understood. In search of the genomic database, more than 830 open reading frames （ORFs） were found to encode transmembrane proteins of P. chrysogenum. In order to investigate their roles on penicillin production, one of them （penT） was selected and cloned. The deduced protein ofpenTbelongs to the major facilitator superfamily （MFS） and contains 12 transmembrane spanning domains （TMS）. During fermentation, the transcription of penT was greatly induced by penicillin precursors phenylacetic acid （PAA） and phenoxyacetic acid （POA）. Knock-down of penT resulted in significant decrease of penicillin production, while over-expression of penT under the promoter of trpC enhanced the penicillin production. Introduction of an additional penT in the wild-type strain of P. chrysogenurn doubled the penicillin production and enhanced the sensitivity of P. chrysogenum to the penicillin precursors PAA or POA. These results indicate that penT stimulates penicillin production probably through enhancing the translocation of penicillin precursors across fungal cellular membrane. Penicillin is historically important as the first discovered drug against bacterial infections in human. Although the penicillin biosyn- thetic pathway and regulatory mechanism have been well studied in Penicillium chrysogenum, the compartmentation and molecular transport of penicillin or its precursors are still poorly understood. In search of the genomic database, more than 830 open reading frames （ORFs） were found to encode transmembrane proteins of P. chrysogenum. In order to investigate their roles on penicillin production, one of them （penT） was selected and cloned. The deduced protein ofpenTbelongs to the major facilitator superfamily （MFS） and contains 12 transmembrane spanning domains （TMS）. During fermentation, the transcription of penT was greatly induced by penicillin precursors phenylacetic acid （PAA） and phenoxyacetic acid （POA）. Knock-down of penT resulted in significant decrease of penicillin production, while over-expression of penT under the promoter of trpC enhanced the penicillin production. Introduction of an additional penT in the wild-type strain of P. chrysogenurn doubled the penicillin production and enhanced the sensitivity of P. chrysogenum to the penicillin precursors PAA or POA. These results indicate that penT stimulates penicillin production probably through enhancing the translocation of penicillin precursors across fungal cellular membrane.
Penicillin is historically important as the first discovered drug against bacterial infections in human. Although the penicillin biosyn- thetic pathway and regulatory mechanism have been well studied in Penicillium chrysogenum, the compartmentation and molecular transport of penicillin or its precursors are still poorly understood. In search of the genomic database, more than 830 open reading frames （ORFs） were found to encode transmembrane proteins of P. chrysogenum. In order to investigate their roles on penicillin production, one of them （penT） was selected and cloned. The deduced protein ofpenTbelongs to the major facilitator superfamily （MFS） and contains 12 transmembrane spanning domains （TMS）. During fermentation, the transcription of penT was greatly induced by penicillin precursors phenylacetic acid （PAA） and phenoxyacetic acid （POA）. Knock-down of penT resulted in significant decrease of penicillin production, while over-expression of penT under the promoter of trpC enhanced the penicillin production. Introduction of an additional penT in the wild-type strain of P. chrysogenurn doubled the penicillin production and enhanced the sensitivity of P. chrysogenum to the penicillin precursors PAA or POA. These results indicate that penT stimulates penicillin production probably through enhancing the translocation of penicillin precursors across fungal cellular membrane. Penicillin is historically important as the first discovered drug against bacterial infections in human. Although the penicillin biosyn- thetic pathway and regulatory mechanism have been well studied in Penicillium chrysogenum, the compartmentation and molecular transport of penicillin or its precursors are still poorly understood. In search of the genomic database, more than 830 open reading frames （ORFs） were found to encode transmembrane proteins of P. chrysogenum. In order to investigate their roles on penicillin production, one of them （penT） was selected and cloned. The deduced protein ofpenTbelongs to the major facilitator superfamily （MFS） and contains 12 transmembrane spanning domains （TMS）. During fermentation, the transcription of penT was greatly induced by penicillin precursors phenylacetic acid （PAA） and phenoxyacetic acid （POA）. Knock-down of penT resulted in significant decrease of penicillin production, while over-expression of penT under the promoter of trpC enhanced the penicillin production. Introduction of an additional penT in the wild-type strain of P. chrysogenurn doubled the penicillin production and enhanced the sensitivity of P. chrysogenum to the penicillin precursors PAA or POA. These results indicate that penT stimulates penicillin production probably through enhancing the translocation of penicillin precursors across fungal cellular membrane.
基金
supported by the grants from the Ministry of Science and Technology of China(Nos.2009CB118905 and 2010ZX09401-403)
the Knowledge Innovation Program of the Chinese Academy of Sciences(Nos.KSCX2-EW-G-6 and KSCX2-EW-J-6)
