''Acidipropionibacterium timonense'' (''A. timonense)'' is a

bacterium 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 a ...

from the genus of ''

Acidipropionibacterium ''Acidipropionibacterium'' is a bacterial genus from the family of Propionibacteriaceae The Propionibacteriaceae are a family of Gram-positive bacteria In bacteriology, gram-positive bacteria are bacteria that give a positive result in the ...

''.

Discovery

''A. timonense'' was discovered in 2019 during a

macrobiotic A macrobiotic diet (or macrobiotics) is a fad diet based on ideas about types of food drawn from Zen Buddhism. The diet tries to balance the supposed yin and yang elements of food and cookware. Major principles of macrobiotic diets are to reduce ...

study of the breast milk of 4 unrelated healthy mothers in

Mali Mali (; ), officially the Republic of Mali,, , ff, 𞤈𞤫𞤲𞥆𞤣𞤢𞥄𞤲𞤣𞤭 𞤃𞤢𞥄𞤤𞤭, Renndaandi Maali, italics=no, ar, جمهورية مالي, Jumhūriyyāt Mālī is a landlocked country in West Africa. Ma ...

. Alongside ''A. timonense, Lactimicrobium massiliense'', '' Anaerolactibacter massiliensis'', and '' Galactobacillus timonensis'' were also discovered. These four species were first isolated in breast milk, making them the first species since '' Streptococcus lactarius'' to be discovered by this method. The name '''timonense was to signify the French quarter of La Timone located in

Marseille Marseille ( , , ; also spelled in English as Marseilles; oc, Marselha ) is the prefecture of the French department of Bouches-du-Rhône and capital of the Provence-Alpes-Côte d'Azur region. Situated in the camargue region of southern Fran ...

, the location in which the species was first isolated and discovered.

Taxonomy and Evolution

For

phylogenetic In biology, phylogenetics (; from Greek φυλή/ φῦλον [] "tribe, clan, race", and wikt:γενετικός, γενετικός [] "origin, source, birth") is the study of the evolutionary history and relationships among or within groups o ...

analysis,

16S ribosomal RNA 16 S ribosomal RNA (or 16 S rRNA) is the RNA component of the 30S subunit of a prokaryotic ribosome ( SSU rRNA). It binds to the Shine-Dalgarno sequence and provides most of the SSU structure. The genes coding for it are referred to as 16S r ...

PCR PCR or pcr may refer to: Science * Phosphocreatine, a phosphorylated creatine molecule * Principal component regression, a statistical technique Medicine * Polymerase chain reaction ** COVID-19 testing, often performed using the polymerase chain r ...

was used to identity and classify ''A. timonense.'' Genetic classification of 16S RNA found that '' L. massiliense'', '' A. massiliensis'', and '' G. timonensis'' were closely related, while ''A. timonense'' was more closely related to ''

Cutibacterium acnes ''Cutibacterium acnes'' (formerly ''Propionibacterium acnes'') is the relatively slow-growing, typically aerotolerant anaerobic, gram-positive bacterium (rod) linked to the skin condition of acne; it can also cause chronic blepharitis and endopht ...

Cutibacterium avidum ''Cutibacterium'' is a bacterial genus from the family of Propionibacteriaceae The Propionibacteriaceae are a family of Gram-positive bacteria In bacteriology, gram-positive bacteria are bacteria that give a positive result in the Gram stai ...

,'' and ''

Cutibacterium granulosum Cutibacterium granulosum is a bacterium that may stimulate the immune system to fight cancer Cancer is a group of diseases involving abnormal cell growth with the potential to invade or spread to other parts of the body. These contrast w ...

. A. timonense'' is also related to the ''

propionibacterium ''Propionibacterium'' is a gram-positive, anaerobic, rod-shaped genus of bacteria named for their unique metabolism: They are able to synthesize propionic acid by using unusual transcarboxylase enzymes. Its members are primarily facultative pa ...

'' genus, and is part of the larger ''

propionibacteriaceae The Propionibacteriaceae are a family of Gram-positive bacteria In bacteriology, gram-positive bacteria are bacteria that give a positive result in the Gram stain test, which is traditionally used to quickly classify bacteria into two broad ca ...

family Family (from la, familia) is a group of people related either by consanguinity (by recognized birth) or affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its members and of society. Idea ...

. A phylogenetic tree comparing ''A. timonense'' to genetically similar species is shown below:

Description and Cell Biology

''A. timonense'' is a

gram-positive In bacteriology, gram-positive bacteria are bacteria that give a positive result in the Gram stain test, which is traditionally used to quickly classify bacteria into two broad categories according to their type of cell wall. Gram-positive bac ...

, non-endospore forming,

non-motile Sessility is the biological property of an organism describing its lack of a means of self-locomotion. Sessile organisms for which natural '' motility'' is absent are normally immobile. This is distinct from the botanical concept of sessility, ...

, and faculative anaerobic bacterium. The bacteria is 0.8 μm in width and 1.2 μm long with a

coccobacilli A coccobacillus (plural coccobacilli), or bacilluscocco, is a type of bacterium with a shape intermediate between cocci (spherical bacteria) and bacilli (rod-shaped bacteria). Coccobacilli, then, are very short rods which may be mistaken for cocci ...

(short rod) shape. The

cell wall A cell wall is a structural layer surrounding some types of cells, just outside the cell membrane. It can be tough, flexible, and sometimes rigid. It provides the cell with both structural support and protection, and also acts as a filtering mec ...

is primarily made up of 15-carbon fatty acid chains. ''A. timonense'' has been observed to grow between 28°C and 45°C, with optimal growth occuring at 37°C. ''A. timonense's'' pH range is between 6.5 to 8.0, with optimum growth at 7.5. Colonies of ''A. timonense'' are circular, cream-colored, and non-haemolytic. Metabolically, ''A. timonense'' is capable of hydrolysing

aesculin Aesculin, also called æsculin or esculin, is a coumarin glucoside that naturally occurs in the trees horse chestnut (''Aesculus hippocastanum''), California buckeye (''Aesculus californica''), prickly box (''Bursaria spinosa''), and daphnin ( ...

and

gelatine Gelatin or gelatine (from la, gelatus meaning "stiff" or "frozen") is a translucent, colorless, flavorless food ingredient, commonly derived from collagen taken from animal body parts. It is brittle when dry and rubbery when moist. It may also ...

, and

ferments 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 p ...

cellobiose Cellobiose is a disaccharide with the formula (C6H7(OH)4O)2O. It is classified as a reducing sugar. In terms of its chemical structure, it is derived from the condensation of a pair of β-glucose molecules forming a β(1→4) bond. It can be hy ...

maltose } Maltose ( or ), also known as maltobiose or malt sugar, is a disaccharide formed from two units of glucose joined with an α(1→4) bond. In the isomer isomaltose, the two glucose molecules are joined with an α(1→6) bond. Maltose is the tw ...

glucose Glucose is a simple sugar with the molecular formula . Glucose is overall the most abundant monosaccharide, a subcategory of carbohydrates. Glucose is mainly made by plants and most algae during photosynthesis from water and carbon dioxide, usi ...

glycerol Glycerol (), also called glycerine in British English and glycerin in American English, is a simple triol compound. It is a colorless, odorless, viscous liquid that is sweet-tasting and non-toxic. The glycerol backbone is found in lipids know ...

sucrose Sucrose, a disaccharide, is a sugar composed of glucose and fructose subunits. It is produced naturally in plants and is the main constituent of white sugar. It has the molecular formula . For human consumption, sucrose is extracted and refi ...

, and

trehalose Trehalose (from Turkish '' tıgala'' – a sugar derived from insect cocoons + -ose) is a sugar consisting of two molecules of glucose. It is also known as mycose or tremalose. Some bacteria, fungi, plants and invertebrate animals synthesize it ...

, along with most other sugars. ''A. timonense'' is unable to produce

urease Ureases (), functionally, belong to the superfamily of amidohydrolases and phosphotriesterases. Ureases are found in numerous bacteria, fungi, algae, plants, and some invertebrates, as well as in soils, as a soil enzyme. They are nickel-containi ...

and, thus, cannot reduce nitrates. Additionally, it cannot ferment

arabinose Arabinose is an aldopentose – a monosaccharide containing five carbon atoms, and including an aldehyde (CHO) functional group. For biosynthetic reasons, most saccharides are almost always more abundant in nature as the "D"-form, or structural ...

rhamnose Rhamnose (Rha, Rham) is a naturally occurring deoxy sugar. It can be classified as either a methyl- pentose or a 6-deoxy- hexose. Rhamnose predominantly occurs in nature in its L-form as L-rhamnose (6-deoxy-L- mannose). This is unusual, since mo ...

, sorbitol and

xylose Xylose ( grc, ξύλον, , "wood") is a sugar first isolated from wood, and named for it. Xylose is classified as a monosaccharide of the aldopentose type, which means that it contains five carbon atoms and includes an aldehyde functional gro ...

References

Propionibacteriales Bacteria described in 2019 {{Propionibacterineae-stub