''Aquicella'' is a genus of

Gram-negative Gram-negative bacteria are bacteria that, unlike gram-positive bacteria, do not retain the crystal violet stain used in the Gram staining method of bacterial differentiation. Their defining characteristic is that their cell envelope consists ...

rod-shaped cells and filaments in the family ''

Coxiellaceae The Coxiellaceae are a family in the order Legionellales. ''Coxiella burnetii'' is the best-described species in this group. The bacterium ''Rickettsiella melolonthae'' was initially assigned to the ''Coxiellaceae'', but is considered part of t ...

'' from the order ''

Legionellales The ''Legionellales'' are an order of '' Pseudomonadota'' ("Proteobacteria"). Like all ''Pseudomonadota'', they are Gram-negative.George M. Garrity: '' Bergey's Manual of Systematic Bacteriology''. 2. Auflage. Springer, New York, 2005, Volume 2: ...

''. The type species of this genus is ''Aquicella lusitana.'' The name ''Aquicella'' is composed of the Latin term ''aqua'' (referring to water) and the Latin term ''cella'' (referring to a chamber, closet, or cabinet, or in biology, a cell). Together, the name ''Aquicella'' translates to a cell from water.

Biochemical Characteristics and Molecular Signatures

Members of this genus grow in

protozoa Protozoa (: protozoan or protozoon; alternative plural: protozoans) are a polyphyletic group of single-celled eukaryotes, either free-living or parasitic, that feed on organic matter such as other microorganisms or organic debris. Historically ...

and can be isolated from hydrothermal areas. All members are strictly

aerobic Aerobic means "requiring air," in which "air" usually means oxygen. Aerobic may also refer to * Aerobic exercise, prolonged exercise of moderate intensity * Aerobics, a form of aerobic exercise * Aerobic respiration, the aerobic process of cellu ...

, non-motile, do not produce spores and are oxidase and catalase negative. ''Aquicella'' species can grow in temperatures ranging from 30 °C to 43 °C and require a neutral pH and growth media containing activated charcoal and a-ketoglutarate. Colonies appear whitish with a pink or blue sheen. Analyses of genome sequences from ''Aquicella'' species identified six

conserved signature indels Conserved signature inserts and deletions (CSIs) in protein sequences provide an important category of molecular markers for understanding phylogenetic relationships. CSIs, brought about by rare genetic changes, provide useful phylogenetic markers ...

(CSIs) as exclusively present in members of this genus in the proteins 30S ribosomal protein S6-L-glutamate ligase, crossover junction endodeoxyribonuclease RuvC, Tim44 domain-containing protein, pyruvate dehydrogenase (acetyl-transferring), homodimeric type,

c-type cytochrome Cytochromes ''c'' (cyt ''c'', c-type cytochromes) cytochromes, or heme-containing proteins, that have heme C Covalent bond, covalently attached to the peptide backbone via one or two thioether bonds. These bonds are in most cases part of a specifi ...

and response regulator transcription factor. These CSIs serve to molecularly demarcate this genus from other ''Coxiellaceae'' species and all other bacteria.

References

{{Taxonbar, from=Q21220451 Bacteria genera Legionellales