Functional characterization of new polyketide synthase genes involved in ochratoxin A biosynthesis in Aspergillus ochraceus fc-1

16Citations
Citations of this article
21Readers
Mendeley users who have this article in their library.

Abstract

Ochratoxin A (OTA), a potentially carcinogenic mycotoxin which contaminates grains, is produced by several Aspergillus species. A comparative sequence analysis of the OTA-producing Aspergillus ochraceus fc-1 strain and other Aspergillus species was performed. Two new OTA-related polyketide synthase (PKS) (AoOTApks) genes were identified. The predicted amino acid sequence of AoOTApks-1 displayed high similarity to previously identified PKSs from OTA-producing A. carbonarius ITEM 5010 (67%; [PI] No. 173482) and A. niger CBS 513.88 (62%; XP_001397313). However, the predicted amino acid sequence of AoOTApks-2 displayed lower homology with A. niger CBS 513.88 (38%) and A. carbonarius ITEM 5010 (28%). A phylogenetic analysis of the β-ketosynthase and acyl-transferase domains of the AoOTApks proteins indicated that they shared a common origin with other OTA-producing species, such as A. carbonarius, A. niger, and A. westerdijkiae. A real-time reverse-transcription PCR analysis showed that the expression of AoOTApks-1 and -2 was positively correlated with the OTA concentration. The pks gene deleted mutants ΔAoOTApks-1 and ΔAoOTApks-2 produced nil and lesser OTA than the wild-type strain, respectively. Our study suggests that AoOTApks-1 could be involved in OTA biosynthesis, while AoOTApks-2 might be indirectly involved in OTA production.

Cite

CITATION STYLE

APA

Wang, L., Wang, Y., Wang, Q., Liu, F., Selvaraj, J. N., Liu, L., … Liu, Y. (2015). Functional characterization of new polyketide synthase genes involved in ochratoxin A biosynthesis in Aspergillus ochraceus fc-1. Toxins, 7(8), 2723–2738. https://doi.org/10.3390/toxins7082723

Register to see more suggestions

Mendeley helps you to discover research relevant for your work.

Already have an account?

Save time finding and organizing research with Mendeley

Sign up for free