''Halorubrum lacusprofundi'' is a rod-shaped, halophilic Archaeon 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 ''Haloferacales ...

. 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, it contains the geographic South Pole. Antarctica is the fifth-largest contine ...

in the 1980s.

Genome

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

genome In the fields of molecular biology and genetics, 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 ge ...

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 long DNA molecule with part or all of the genetic material of an organism. In most chromosomes the very long thin DNA fibers are coated with packaging proteins; in eukaryotic cells the most important of these proteins are ...

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; how ...

. 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 (from , ; "...Wilhelm Johannsen coined the word gene to describe the Mendelian units of heredity..." meaning ''generation'' or ''birth'' or ''gender'') can have several different meanings. The Mendelian gene is a ba ...

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, which takes place via a mechanism that uses vesicle-enclosed virus-like particles.

Research

Its β-galactosidase

enzyme Enzymes () are proteins that act as biological catalysts by accelerating chemical reactions. The molecules upon which enzymes may act are called substrates, and the enzyme converts the substrates into different molecules known as products. A ...

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

References

Euryarchaeota {{archaea-stub