Tannin-degrading bacteria with cellulase activity isolated from the cecum of the Qinghai-Tibet plateau zokor (Myospalax baileyi)

Abstract

Tannins, which are polyphenols present in various plants, have anti-nutritional activity; however, their negative effects are mitigated by the presence of tannin-degrading microorganisms in the gastrointestinal tract of animals. This has never been investigated in the plateau zokor (Myospalax baileyi) – the predominant small herbivore in the alpine meadow ecosystem of Qinghai Province, China – which consumes tannin-rich herbaceous plants. Tannase activity in the feces of the plateau zokor increased from June to August corresponding to the increase in hydrolyzable tannin concentrations in plants during this period, and three tannin-degrading facultative anaerobic strains (designated as E1, E2, and E3) were isolated from the cecum of these animals. Sequencing of the 16S rDNA gene identified isolates of strain E1 as belonging to the genus Enterococcus, and E2 and E3 to the genus Bacillus. All of the bacteria had cellulose-degrading capacity. This study provides the first evidence of symbiotic bacterial strains that degrade tannic acid and cellulose in the cecum of plateau zokor.

Keywords:

• Myospalax baileyi
• bacteria
• tannase
• cellulase
• 16S rDNA

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This work was supported by the National Basic Research Program [“973” Program] of China [grant number 2007CB109102]; National Science Foundation of China [grant number 31272320]; the Priority Academic Program Development of Jiangsu Higher Education Institutions (PAPD); and Open Project of Jiangsu Key Laboratory of Zoonosis [grant number R1102].