Natural habitats of Prevotella sp. include the rumen and hindgut of cattle, sellckchem sheep, and humans, where they help break down protein [32] and carbohydrate [33]. However, some species of this genus are known to be opportunistic pathogens to humans [34]. Proteobacteria were the second predominant phylum in the pygmy loris gastrointestinal tract with Pseudomonadales as the primary contributor to the Proteobacteria populations, followed by Enterobacteriales and Burkholderiales. The major genus in the Proteobacteria phylum is Pseudomonas, which is consistent with previous 16S rRNA gene-based data [7]. Several microbes belonging to the genus of Pseudomonas have a very diverse metabolism, including the ability to degrade organic solvents such as toluene [35] and phenol [36], [37].

This ability may benefit the pygmy loris, given that they consume several toxic and pungent insects. Pseudomonas fluorescens was the predominant species among the Pseudomonas in the pygmy loris metagenome. P. fluorescens is a common Gram-negative bacterium that can be found in the low section of the human digestive tract [38]. Similarly, Clostridia and Bacilli are the primary contributors to the Firmicutes populations. However, various genera were found in the pygmy loris metagenome than in the 16S rRNA gene [7] (Table S2). Clostridiales is the dominant order in Clostridia, which includes well-known gut bacteria, Faecalibacterium prausnitzii. F. prausnitzii is the most important n-butyrate producing gut bacterium with well-known effects on host energy metabolism and mucosal integrity [39].

A distinctive feature of the pygmy loris metagenome is the abundance of phylum Verrucomicrobia, particularly the members of the genus Akkermansia; this abundance was unexpected and far greater than in humans (Table S2, Figure 2). The dominant species in the Verrucomicrobia phylum was Akkermansia muciniphila, which are common members of the human gut microbiota evident in human infants [40]. These mucin-degrading bacteria are related to normal mucosa development. Moreover, the Akkermansia species may have a role in maintaining intestinal integrity. Figure 2 Phylogenetic clustering of pygmy loris, human, mouse, canine, cow, and chicken gastrointestinal metagenomes. Eukaryota were a minor constituent (~4.0%) in the pygmy loris metagenome. Species of Blastocystis were also represented in small quantities (<0.

01%) in the pygmy loris metagenome. These species have been reported as the most commonly occurring micro-eukaryote in human feces [41], [42]. In addition, the presence of Blastocystis has been linked to a number of gut-related diseases. Some of these diseases could be the outcome of the predation of beneficial bacteria by Blastocystis in light of the similar observations in ruminant Carfilzomib cattle and their communalistic protozoa [43]. Fungi have very low abundance sequences (0.