Bioplastic reservoir of diverse bacterial communities revealed along altitude gradient of Pangi-Chamba trans-Himalayan region

Abstract

Himalaya hosts a unique environment for microbial ecology. The present study aimed to explore the bioplastic producing bacterial communities along altitude gradient of Pangi-Chamba trans-Himalayan (PCH) region. A total of four hundred eleven bacteria were isolated and seventy characterized at the molecular level for potential polyhydroxyalkanoates (PHA) producers. The most abundant phylum for PHA synthesis was Proteobacteria (73%), followed by Actinobacteria (11%), Firmicutes (10%), and Bacteroidetes (6%). However, at the genus level, Pseudomonas and Janthinobacterium were dominantly reported. Also, the ability to synthesize PHA was reported for the first time for few genera such as Collimonas, Pseudarthrobacter, and Paenarthrobacter. Phylogenetic analysis of partial 16S rDNA and phaC genes revealed conservation in phaC and possibility of horizontal gene transfer among distant taxa. Furthermore, GCMS also confirmed the ability of potential bacterial isolates to synthesize PHA. In fact, we found that PHA positive bacteria are dominant in the high altitude of Himalaya, suggesting the vital role of PHA in bacterial adaptation and survival. Together, these findings had revealed the rich bacterial diversity and genetic machinery for PHA synthesis which does have potential for further utilization in the commercial applications.