Dataset Information

Identification of an essential regulator controlling the production of raw-starch-digesting glucoamylase in Penicillium oxalicum.

ABSTRACT:

Background

Raw-starch-digesting glucoamylases (RSDGs) from filamentous fungi have great commercial values in starch processing; however, the regulatory mechanisms associated with their production in filamentous fungi remain unknown. Penicillium oxalicum HP7-1 isolated by our laboratory secretes RSDG with suitable properties but at low production levels. Here, we screened and identified novel regulators of RSDG gene expression in P. oxalicum through transcriptional profiling and genetic analyses.

Results

Penicillium oxalicum HP7-1 transcriptomes in the presence of glucose and starch, respectively, used as the sole carbon source were comparatively analyzed, resulting in screening of 23 candidate genes regulating the expression of RSDG genes. Following deletion of 15 of the candidate genes in the parental P. oxalicum strain ∆PoxKu70, enzymatic assays revealed five mutants exhibiting significant reduction in the production of raw-starch-digesting enzymes (RSDEs). The deleted genes (POX01907, POX03446, POX06509, POX07078, and POX09752), were the first report to regulate RSDE production of P. oxalicum. Further analysis revealed that ∆POX01907 lost the most RSDE production (83.4%), and that POX01907 regulated the expression of major amylase genes, including the RSDG gene POX01356/PoxGA15A, a glucoamylase gene POX02412, and the α-amylase gene POX09352/Amy13A, during the late-stage growth of P. oxalicum.

Conclusion

Our results revealed a novel essential regulatory gene POX01907 encoding a transcription factor in controlling the production of RSDE, regulating the expression of an important RSDG gene POX01356/PoxGA15A, in P. oxalicum. These results provide insight into the regulatory mechanism of fungal amylolytic enzyme production.

SUBMITTER: Zhang MY

PROVIDER: S-EPMC6318894 | biostudies-literature | 2019

REPOSITORIES: biostudies-literature

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Identification of an essential regulator controlling the production of raw-starch-digesting glucoamylase in <i>Penicillium oxalicum</i>.

Zhang Mei-Yuan MY Zhao Shuai S Ning Yuan-Ni YN Fu Li-Hao LH Li Cheng-Xi CX Wang Qi Q You Ran R Wang Chen-Ying CY Xu Han-Nan HN Luo Xue-Mei XM Feng Jia-Xun JX

Biotechnology for biofuels 20190104

<h4>Background</h4>Raw-starch-digesting glucoamylases (RSDGs) from filamentous fungi have great commercial values in starch processing; however, the regulatory mechanisms associated with their production in filamentous fungi remain unknown. <i>Penicillium oxalicum</i> HP7-1 isolated by our laboratory secretes RSDG with suitable properties but at low production levels. Here, we screened and identified novel regulators of RSDG gene expression in <i>P</i>. <i>oxalicum</i> through transcriptional pr ...[more]

PMID: 30622649

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