Complete genome sequence of Halomonas alkaliantarctica MSP3 isolated from marine sediment, Jeju Island.

As a moderate halophilic-heterotrophic bacterium, Halomonas alkaliantarctica MSP3 was isolated from marine sediment located in Jeju island, South Korea. The complete genome of strain MSP3 was sequenced and analyzed to reveal its genetic features and metabolic potential. The genome size of MSP3 was about 4.23 Mbp with 54.7% G + C content, and it contained 3811 protein-coding sequences and 79 RNA genes (61 tRNA and 18 rRNA). According to the genome annotation, it was revealed that the strain MSP3 harbors genes encoding for urease and urea transporters, which play a crucial role in the process of urea degradation and utilization. In addition, it is noteworthy that the MSP3 strain possesses genes encoding for both cytochrome c oxidase and cytochrome bd oxidase, thereby conferring upon it the ability to adapt to various levels of oxygen (oxic to microoxic) and to execute denitrification processes in the absence of oxygen. Moreover, it was observed that strain MSP3 had genes for the glyoxylate cycle, which is an alternative pathway to the TCA cycle. Furthermore, it was observed that the MSP3 strain exhibited the ability to thrive across a diverse spectrum of NaCl concentrations, ranging from 2% to 10% (w/v). Collectively, strain MSP3 may possess an advantage over competitors within the marine ecosystem, particularly in conditions where carbon substrates are restricted. The genomic-based assumption could potentially be substantiated by the presence of a multitude of transporter genes within the genome.