Hu Z, Liu S, Zhou X, Liu Z, Li T, Yu S, Zhang X, Xu Z. Morphological variation and expressed sequence tags-simple sequence repeats-based genetic diversity of
Aspergillus cristatus in Chinese dark tea.
Front Microbiol 2024;
15:1390030. [PMID:
38887709 PMCID:
PMC11180798 DOI:
10.3389/fmicb.2024.1390030]
[Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2024] [Accepted: 05/22/2024] [Indexed: 06/20/2024] Open
Abstract
Introduction
Aspergillus cristatus is a homothallic fungus that is used in the natural fermentation process of Chinese Fuzhuan tea and has been linked to the production of bioactive components. However, not much is known about the variations present in the fungus. To understand the variation of the dominant microorganism, A. cristatus, within dark tea, the present study investigated the genetic and morphological diversity of 70 A. cristatus collected across six provinces of China.
Methods
Expressed sequence tags-simple sequence repeats (EST-SSR) loci for A. cristatus were identified and corresponding primers were developed. Subsequently, 15 specimens were selected for PCR amplification.
Results
The phylogenetic tree obtained revealed four distinct clusters with a genetic similarity coefficient of 0.983, corresponding to previously identified morphological groups. Five strains (A1, A11, B1, D1, and JH1805) with considerable differences in EST-SSR results were selected for further physiological variation investigation. Microstructural examinations revealed no apparent differentiation among the representative strains. However, colony morphology under a range of culture media varied substantially between strains, as did the extracellular enzymatic activity (cellulase, pectinase, protease, and polyphenol oxidase); the data indicate that there are differences in physiological metabolic capacity among A. cristatus strains.
Discussion
Notably, JH1805, B1, and A11 exhibited higher enzymatic activity, indicating their potential application in the production of genetically improved strains. The findings provide valuable insights into species identification, genetic diversity determination, and marker-assisted breeding strategies for A. cristatus.
Collapse