''Komagataeibacter xylinus'' is a

species In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriate s ...

bacteria Bacteria (; singular: bacterium) are ubiquitous, mostly free-living organisms often consisting of one biological cell. They constitute a large domain of prokaryotic microorganisms. Typically a few micrometres in length, bacteria were among ...

best known for its ability to produce

cellulose Cellulose is an organic compound with the formula , a polysaccharide consisting of a linear chain of several hundred to many thousands of β(1→4) linked D-glucose units. Cellulose is an important structural component of the primary cell wall ...

, specifically

bacterial cellulose Bacterial cellulose is an organic compound with the formula produced by certain types of bacteria. While cellulose is a basic structural material of most plants, it is also produced by bacteria, principally of the genera ''Acetobacter'', Sarcina ( ...

History and taxonomy

The species was first described in 1886 by

Adrian John Brown Adrian John Brown, FRS (27 April 1852 – 2 July 1919) was a British Professor of Malting and Brewing at the University of Birmingham and a pioneer in the study of enzyme kinetics. He was born at Burton-on-Trent, Staffordshire to Edwin Brown, ...

, who identified the bacteria while studying

fermentation Fermentation is a metabolic process that produces chemical changes in organic substrates through the action of enzymes. In biochemistry, it is narrowly defined as the extraction of energy from carbohydrates in the absence of oxygen. In food ...

. Brown gave the species the name ''Bacterium xylinum''. It has since been known by several other names, mainly ''Acetobacter xylinum'' and ''Gluconacetobacter xylinus''. It was given its current name, with the establishment of the new

genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In the hierarchy of biological classification, genus com ...

Komagataeibacter ''Komagataeibacter'' is a genus of bacteria in the family Acetobacteraceae. It was described in 2012 by Yamada ''et al''. The type species is ''Komagataeibacter xylinus''. Species The genus contains the following species: * '' Komagataeibacte ...

'', in 2012. It is the

type species In zoological nomenclature, a type species (''species typica'') is the species name with which the name of a genus or subgenus is considered to be permanently taxonomically associated, i.e., the species that contains the biological type specimen ...

of the genus.

Genome and metabolism

''K. xylinus'' is a member of the acetic acid bacteria, a group of

Gram-negative Gram-negative bacteria are bacteria that do not retain the crystal violet stain used in the Gram staining method of bacterial differentiation. They are characterized by their cell envelopes, which are composed of a thin peptidoglycan cell wall ...

aerobic bacteria that produce

acetic acid Acetic acid , systematically named ethanoic acid , is an acidic, colourless liquid and organic compound with the chemical formula (also written as , , or ). Vinegar is at least 4% acetic acid by volume, making acetic acid the main component ...

during

. ''K. xylinus'' is unusual among the group in also producing

Bacterial cellulose Bacterial cellulose is an organic compound with the formula produced by certain types of bacteria. While cellulose is a basic structural material of most plants, it is also produced by bacteria, principally of the genera ''Acetobacter'', Sarcina ( ...

(also sometimes known as nanocellulose) is involved in the formation of

biofilm A biofilm comprises any syntrophic consortium of microorganisms in which cells stick to each other and often also to a surface. These adherent cells become embedded within a slimy extracellular matrix that is composed of extracellular ...

s. It is chemically identical to plant cellulose, but has distinct physical structure and properties. 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 ...

of a cellulose-deficient strain of ''K. xylinus'' was sequenced in 2011, and followed by the genomes of cellulose-producing strains in 2014 and 2018. The first cellulose-producing strain had a genome consisting of one

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 ...

3.4 megabase pairs and five

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 ...

s, of which one is a "megaplasmid" of about 330 kilobase pairs. Key genes related to cellulose production occur in the four-gene operon ''bcsABCD'', which codes for the four subunits of the

cellulose synthase The UDP-forming form of cellulose synthase () is the main enzyme that produces cellulose. Systematically, it is known as ''UDP-glucose:(1→4)-β-D-glucan 4-β-D-glucosyltransferase'' in enzymology. It catalyzes the chemical reaction: : UDP-g ...

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 ...

. All four genes are required for efficient cellulose production ''in vivo'', although BcsA and BscB are sufficient ''

in vitro ''In vitro'' (meaning in glass, or ''in the glass'') studies are performed with microorganisms, cells, or biological molecules outside their normal biological context. Colloquially called "test-tube experiments", these studies in biology an ...

''. Several other genes in the ''K. xylinus'' genome are also involved in cellulose production and regulation, including a

cellulase Cellulase (EC 3.2.1.4; systematic name 4-β-D-glucan 4-glucanohydrolase) is any of several enzymes produced chiefly by fungi, bacteria, and protozoans that catalyze cellulolysis, the decomposition of cellulose and of some related polysaccharide ...

enzyme.

Uses and significance

''K. xylinus'' was used for a long time as a

model organism A model organism (often shortened to model) is a non-human species that is extensively studied to understand particular biological phenomena, with the expectation that discoveries made in the model organism will provide insight into the workin ...

for the study of cellulose production in

plant Plants are predominantly photosynthetic eukaryotes of the kingdom Plantae. Historically, the plant kingdom encompassed all living things that were not animals, and included algae and fungi; however, all current definitions of Plantae exclud ...

s. It is also studied in its own right to explore bacterial

production, cell-cell communication, and other topics of interest. Production of bacterial cellulose for industrial uses has been the subject of extensive research, but is limited by productivity and scalability. ''Acetobacter xylinus'' is found to be the main microorganism in the culture of Kombucha. ''K. xylinus'' is also traditionally used in the

Philippines The Philippines (; fil, Pilipinas, links=no), officially the Republic of the Philippines ( fil, Republika ng Pilipinas, links=no), * bik, Republika kan Filipinas * ceb, Republika sa Pilipinas * cbk, República de Filipinas * hil, Republ ...

for the production of jelly-like ''

nata de piña ''Nata de piña'' ("cream of pineapple" in Philippine Spanish, Spanish), also marketed as pineapple gel or pineapple gelatin, is a chewy, translucent, Fruit preserves, jelly-like food produced by the fermentation (food), fermentation of pineapple j ...

'' and ''

nata de coco ''Nata de coco'', also marketed as coconut gel, is a chewy, translucent, jelly-like food produced by the fermentation of coconut water, which gels through the production of microbial cellulose by '' Komagataeibacter xylinus''. Originating i ...

'' desserts, made from pineapple juice and

coconut water Coconut water (also coconut juice) is the clear liquid inside coconuts (fruits of the coconut palm). In early development, it serves as a suspension for the endosperm of the coconut during the nuclear phase of development. As growth continue ...

, respectively. The former has been produced since the 18th century.

References

{{Taxonbar, from=Q25861011 Rhodospirillales Cellulose Bacteria described in 1886