Exploring bacteriome diversity of coral Goniopora sp. and Favia favus from the Gulf of Kutch, Gujarat

Coral reefs are keystone ecosystems, and the ecological success of coral reefs depends on coral-algal symbiosis and healthy coral-bacterial interactions. However, the bacteriome diversity associated with different coral spe-cies in the Gulf of Kutch, Gujarat, remains largely unexplored. In this study, we compared the bacteriome di-versity of reef-building corals Goniopora (G. columna, G. lobata, G. stutchburyi) and Favia (F. favus) collected from the two islands viz. Poshitra (PO) and Pirotan (PI) in the Gulf of Kutch, Gujarat, using metagenomic sequencing of 16S rRNA gene and amplicon sequence variants (ASVs) based multivariate analysis. Heat map and network analyses were performed to explore coral bacteriome co-occurrence patterns, revealing 77 and 33 co-occurring bacterial genera associated with Goniopora sp. and F. favus corals, respectively. Co-occurring bacterial genera play a potential role in biogeochemical cycles like carbon, nitrogen, sulfur, nutrient metabolism, host detoxifi-cation, and association with dinoflagellates of the family Symbiodiniaceae. The majority of the bacterial genera present were frequently found in the corals, where some are predicted to play a significant role in coral resilience and have medicinal and biotechnological applications. These results indicate that the coral type, species dif-ference, and location, in conjunction with environmental niche, play key roles in coral-bacteriome interaction. The present study can also serve as a baseline and pave the way for the conservation and transplantation of coral species in the Gulf of Kutch.