De Novo Genome Assembly and Sequence Analysis of Chlorogloeopsis sp. ULAP01 Isolated from a Copper Mine Tailing Environment

Cyanobacteria play a key role in many ecosystems. Cell-environment interaction has been attributed to their metabolite production, allowing cyanobacteria to adapt and survive under extreme conditions. A strain of cyanobacteria (Chlorogloeopsis sp. ULAP01) isolated from a copper mine tailing site in Ampucao, Benguet, the Philippines, was examined in this study. It aimed to construct the whole genome sequence of the cyanobacterium, characterize it, and compare the assembled genome with the sequences available in the National Center for Biotechnology Information (NCBI) database. The whole genome of Chlorogloeopsis sp. ULAP01 was assembled, constructed, and functionally analyzed. Sequence analysis of the Chlorogloeopsis sp. ULAP01 with the C. fritschii genomes available in the NCBI database was also performed. The assembled genome had a total length of 7.9 Mb, 45 contigs, and 41% GC content. The isolate was identified as putatively Chlorogloeopsis sp. ULAP01 by morphological and molecular characterization through GTDB-Tk results and evolutionary analysis. It forms a separate node from the two known clusters of Chlorogloeopsis, indicating that it may be a separate strain or a new, previously uncharacterized strain or species. Chlorogloeopsis sp. ULAP01 shared 2,019 core genes with the other C. fritschii assemblies in the NCBI database but also possessed a total of 4,449 unique genes, 65.24% of its total annotated genes. It was noted that the strain shared the same core genes, but the accessory genes of Chlorogloeopsis sp. ULAP01 varied widely with the other Chlorogloeopsis sp. in the database. Chlorogloeopsis sp. ULAP01 is the first isolate to be added to NCBI that came from a tropical freshwater ecosystem. The unique specialized genes such as copB, entS, yfeA, and ftsP are involved in cellular processes for survival in a metal-stressed condition that may be responsible for its survival in an extreme environment.