''Halorubrum lacusprofundi'' is a rod-shaped, halophilic

Archaeon Archaea ( ) is a domain of organisms. Traditionally, Archaea only included its prokaryotic members, but this has since been found to be paraphyletic, as eukaryotes are known to have evolved from archaea. Even though the domain Archaea cladis ...

in the family of

Halorubraceae ''Halorubraceae'' is a family of halophilic, chemoorganotrophic or heterotrophic archaea within the order '' Haloferacales.'' The type genus of this family is ''Halorubrum''. Its biochemical characteristics are the same as the order '' Haloferaca ...

. It was first isolated from Deep Lake in

Antarctica Antarctica () is Earth's southernmost and least-populated continent. Situated almost entirely south of the Antarctic Circle and surrounded by the Southern Ocean (also known as the Antarctic Ocean), it contains the geographic South Pole. ...

in the 1980s.

Genome

Several strains of ''H. lacusprofundi'' have been discovered. The

genome A genome is all the genetic information of an organism. It consists of nucleotide sequences of DNA (or RNA in RNA viruses). The nuclear genome includes protein-coding genes and non-coding genes, other functional regions of the genome such as ...

sequencing In genetics and biochemistry, sequencing means to determine the primary structure (sometimes incorrectly called the primary sequence) of an unbranched biopolymer. Sequencing results in a symbolic linear depiction known as a sequence which succ ...

of the strain ACAM 32 was completed in 2008. The organism's genome consists of two circular

chromosome A chromosome is a package of DNA containing part or all of the genetic material of an organism. In most chromosomes, the very long thin DNA fibers are coated with nucleosome-forming packaging proteins; in eukaryotic cells, the most import ...

s and a single circular

plasmid A plasmid is a small, extrachromosomal DNA molecule within a cell that is physically separated from chromosomal DNA and can replicate independently. They are most commonly found as small circular, double-stranded DNA molecules in bacteria and ...

. Chromosome I contains 2,735,295

base pair A base pair (bp) is a fundamental unit of double-stranded nucleic acids consisting of two nucleobases bound to each other by hydrogen bonds. They form the building blocks of the DNA double helix and contribute to the folded structure of both DNA ...

s encoding 2,801

gene In biology, the word gene has two meanings. The Mendelian gene is a basic unit of heredity. The molecular gene is a sequence of nucleotides in DNA that is transcribed to produce a functional RNA. There are two types of molecular genes: protei ...

s and chromosome II contains 525,943 base pairs encoding 522 genes. The single plasmid contains 431,338 base pairs encoding 402 genes. At least one strain of ''H. lacusprofundi'' (R1S1) contains a plasmid (pR1SE) that enables

horizontal gene transfer Horizontal gene transfer (HGT) or lateral gene transfer (LGT) is the movement of genetic material between organisms other than by the ("vertical") transmission of DNA from parent to offspring (reproduction). HGT is an important factor in the e ...

, which takes place via a mechanism that uses vesicle-enclosed

virus-like particle Virus-like particles (VLPs) are molecules that closely resemble viruses, but are non-infectious because they contain no viral genetic material. They can be naturally occurring or synthesized through the individual expression of viral structural pro ...

Research

Its

β-galactosidase β-Galactosidase (EC 3.2.1.23, beta-gal or β-gal; systematic name β-D-galactoside galactohydrolase) is a glycoside hydrolase enzyme that catalyzes hydrolysis of terminal non-reducing β-D-galactose residues in β-D-galactosides. (This enzym ...

enzyme An enzyme () is a protein that acts as a biological catalyst by accelerating chemical reactions. The molecules upon which enzymes may act are called substrate (chemistry), substrates, and the enzyme converts the substrates into different mol ...

has been extensively studied to understand how proteins function in low-temperature, high-saline environments.

References

Euryarchaeota {{archaea-stub