Metagenomic Profile of the Microbiota Communities Associated with Ixodes cordifer Ticks from Cuscuses (Marsupialia: Phalangeridae)

Abstract

This study aims to reveal the metagenomic profile of the microbiota community associated with I. cordifer isolated from cuscuses (Marsupialia: Phalangeridae) on Ambon Island to understand the ecological relationship between ticks, cuscuses, and the microorganisms they carry within a small island ecosystem characterized by high endemism. Current analyses showed that the bacterial community was dominated by the phyla Firmicutes (syn. Bacillota), Proteobacteria, and Actinobacteria. Among these communities, several key species were identified with distinct biological roles, including taxa related to the Bacillus cereus group as dominant bacteria with pathogenic and toxigenic potential that may affect host health and pose zoonotic risks. Conversely, the presence of Bacillus subtilis, Bacillus mycoides, and Brevibacillus laterosporus suggests a potentially protective and mutualistic role, although further functional validation using gene annotation or metatranscriptomic approaches is required. These species are known to produce antimicrobial metabolites and contribute to microbiota stability through a mechanism known as “colonisation resistance”, defined as the ability of resident microbiota to inhibit colonisation by opportunistic and pathogenic bacteria entering through the host or environment. Overall, these findings demonstrate that tick-associated microbiota not only reflect vector physiological adaptation but also have the potential to influence pathogen–host interactions within local ecological systems. Therefore, this study provides initial insights into microbiota dynamics in cuscus-associated ticks from the Wallacea region and underscores the importance of further research on microbiota roles in wildlife health, zoonotic potential, and biotechnological prospects.