''Treponema socranskii'' was isolated from
gum swabs of people with
periodontitis
Periodontal disease, also known as gum disease, is a set of inflammatory conditions affecting the tissues surrounding the teeth. In its early stage, called gingivitis, the gums become swollen and red and may bleed. It is considered the main caus ...
and clinically-induced periodontitis.
It is a
motile
Motility is the ability of an organism to move independently, using metabolic energy.
Definitions
Motility, the ability of an organism to move independently, using metabolic energy, can be contrasted with sessility, the state of organisms th ...
,
helically coiled,
obligate anaerobe
Obligate anaerobes are microorganisms killed by normal atmospheric concentrations of oxygen (20.95% O2). Oxygen tolerance varies between species, with some species capable of surviving in up to 8% oxygen, while others lose viability in environm ...
that grows best at 37 °C, and is a novel member of its genus because of its ability to
ferment
Fermentation is a metabolism, metabolic process that produces chemical changes in organic Substrate (chemistry), substrates through the action of enzymes. In biochemistry, it is narrowly defined as the extraction of energy from carbohydrates in ...
molecules that other ''Treponema'' species cannot.
''T. socranskii''’s growth is positively correlated with gingival
inflammation
Inflammation (from la, wikt:en:inflammatio#Latin, inflammatio) is part of the complex biological response of body tissues to harmful stimuli, such as pathogens, damaged cells, or Irritation, irritants, and is a protective response involving im ...
, which indicates that it is a leading cause of
gingivitis
Gingivitis is a non-destructive disease that causes inflammation of the gums. The most common form of gingivitis, and the most common form of periodontal disease overall, is in response to bacterial biofilms (also called plaque) that is attached ...
and periodontitis.
Discovery and isolation
Robert Smibert, John Johnson, and Richard Ranney isolated ''Treponema socranskii'' in Virginia, 1984.
Volunteers with
periodontitis
Periodontal disease, also known as gum disease, is a set of inflammatory conditions affecting the tissues surrounding the teeth. In its early stage, called gingivitis, the gums become swollen and red and may bleed. It is considered the main caus ...
and clinically-induced periodontitis supplied samples from beneath and above their
gumlines for comparison to samples supplied from volunteers with healthy gums.
The
culture
Culture () is an umbrella term which encompasses the social behavior, institutions, and norms found in human societies, as well as the knowledge, beliefs, arts, laws, customs, capabilities, and habits of the individuals in these groups.Tyl ...
of ''T. socranskii'' were
isolated from the samples supplied from the group of volunteers with periodontitis and clinically-induced periodontitis.
Periodontitis is the lasting harmful
inflammation
Inflammation (from la, wikt:en:inflammatio#Latin, inflammatio) is part of the complex biological response of body tissues to harmful stimuli, such as pathogens, damaged cells, or Irritation, irritants, and is a protective response involving im ...
of the gum line, and clinically-induced periodontitis is the condition in which healthy volunteers stop dental
hygiene
Hygiene is a series of practices performed to preserve health.
According to the World Health Organization (WHO), "Hygiene refers to conditions and practices that help to maintain health and prevent the spread of diseases." Personal hygiene refer ...
to induce periodontitis for controlled scientific
study
Study or studies may refer to:
General
* Education
**Higher education
* Clinical trial
* Experiment
* Observational study
* Research
* Study skills, abilities and approaches applied to learning
Other
* Study (art), a drawing or series of drawi ...
.
Researchers used a
medium
Medium may refer to:
Science and technology
Aviation
*Medium bomber, a class of war plane
* Tecma Medium, a French hang glider design
Communication
* Media (communication), tools used to store and deliver information or data
* Medium of ...
that contained
meat
Meat is animal flesh that is eaten as food. Humans have hunted, farmed, and scavenged animals for meat since prehistoric times. The establishment of settlements in the Neolithic Revolution allowed the domestication of animals such as chic ...
and
salt water
Saline water (more commonly known as salt water) is water that contains a high concentration of dissolved salts (mainly sodium chloride). On the United States Geological Survey (USGS) salinity scale, saline water is saltier than brackish water, ...
that was saturated with
carbon dioxide
Carbon dioxide (chemical formula ) is a chemical compound made up of molecules that each have one carbon atom covalently double bonded to two oxygen atoms. It is found in the gas state at room temperature. In the air, carbon dioxide is transpar ...
to purge the sample of
oxygen
Oxygen is the chemical element with the symbol O and atomic number 8. It is a member of the chalcogen group in the periodic table, a highly reactive nonmetal, and an oxidizing agent that readily forms oxides with most elements as wel ...
.
These samples were cultured in duplicates on selective solid media plates after undergoing
serial dilution
A serial dilution is the stepwise dilution of a substance in solution. Usually the dilution factor at each step is constant, resulting in a geometric progression of the concentration in a logarithmic fashion. A ten-fold serial dilution could be 1 ...
s to ensure purity.
These plates were placed into
GasPak jars to remove any oxygen that may be present in the jar.
The researchers
inoculated colonies
In modern parlance, a colony is a territory subject to a form of foreign rule. Though dominated by the foreign colonizers, colonies remain separate from the administration of the original country of the colonizers, the '' metropolitan state'' ...
from the plates into OTI (oral treponeme isolation) broth and placed them into another GasPak jar.
The jars were kept at 37 °C, and every week the samples were checked using
dark-field microscopy
Dark-field microscopy (also called dark-ground microscopy) describes microscopy methods, in both light and electron microscopy, which exclude the unscattered beam from the image. As a result, the field around the specimen (i.e., where there is ...
.
Taxonomy
The taxonomic
lineage
Lineage may refer to:
Science
* Lineage (anthropology), a group that can demonstrate its common descent from an apical ancestor or a direct line of descent from an ancestor
* Lineage (evolution), a temporal sequence of individuals, populati ...
of ''Treponema socranskii'' is ''Bacteria'', ''Spirochaetes'', ''Spirochaetia'', ''Spirochaetales'', ''Spirochaetaceae'', ''Treponema'', ''socranskii''.
The
subspecies
In biological classification, subspecies is a rank below species, used for populations that live in different areas and vary in size, shape, or other physical characteristics (morphology), but that can successfully interbreed. Not all species ...
were named socranskii, buccale, and paredis.
''Treponema socranskii'' is unique to its
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 ...
due to the combination of a higher average
GC content
In molecular biology and genetics, GC-content (or guanine-cytosine content) is the percentage of nitrogenous bases in a DNA or RNA molecule that are either guanine (G) or cytosine (C). This measure indicates the proportion of G and C bases out o ...
and its lack of need for
serum in its growth media.
Three other species in the genus do not use serum, and have GC contents around 36-39 mol% whereas socranskii has a GC content of 50-52 mol%.
When compared to other cultured ''Treponema'' species:
''denticola'', ''pectinovorum'', and
''vincentii'', a major factor unique to ''socranskii'' is the ability to
ferment
Fermentation is a metabolism, metabolic process that produces chemical changes in organic Substrate (chemistry), substrates through the action of enzymes. In biochemistry, it is narrowly defined as the extraction of energy from carbohydrates in ...
different molecules.
The RapID-ANA system, which is a series of qualitative tests used to identify different anaerobic bacteria, is widely used to distinguish between different
oral
The word oral may refer to:
Relating to the mouth
* Relating to the mouth, the first portion of the alimentary canal that primarily receives food and liquid
**Oral administration of medicines
** Oral examination (also known as an oral exam or oral ...
spirochetes.
This method distinguishes ''socranskii'' from other species because its only positive test is the
alkaline phosphatase
The enzyme alkaline phosphatase (EC 3.1.3.1, alkaline phosphomonoesterase; phosphomonoesterase; glycerophosphatase; alkaline phosphohydrolase; alkaline phenyl phosphatase; orthophosphoric-monoester phosphohydrolase (alkaline optimum), systematic ...
test, while the other species are negative for this test.
Characterization
Optima
The characterization of this organism was done when it was first cultured in 1984.
T. s''ocranskii'' is an
obligate anaerobe
Obligate anaerobes are microorganisms killed by normal atmospheric concentrations of oxygen (20.95% O2). Oxygen tolerance varies between species, with some species capable of surviving in up to 8% oxygen, while others lose viability in environm ...
that grows in media that contains fermentable
carbohydrate
In organic chemistry, a carbohydrate () is a biomolecule consisting of carbon (C), hydrogen (H) and oxygen (O) atoms, usually with a hydrogen–oxygen atom ratio of 2:1 (as in water) and thus with the empirical formula (where ''m'' may or ma ...
s.
The media must also contain
liquid
A liquid is a nearly incompressible fluid that conforms to the shape of its container but retains a (nearly) constant volume independent of pressure. As such, it is one of the four fundamental states of matter (the others being solid, gas, a ...
from an unspecified
rumen
The rumen, also known as a paunch, is the largest stomach compartment in ruminants and the larger part of the reticulorumen, which is the first chamber in the alimentary canal of ruminant animals. The rumen's microbial favoring environment allow ...
or
short chain fatty acids Short-chain fatty acids (SCFAs) are fatty acids with fewer than six carbon atoms. Derived from intestinal microbial fermentation of indigestible foods, SCFAs are the main energy source of colonocytes, making them crucial to gastrointestinal health. ...
.
The preferred
temperature
Temperature is a physical quantity that expresses quantitatively the perceptions of hotness and coldness. Temperature is measured with a thermometer.
Thermometers are calibrated in various temperature scales that historically have relied o ...
for ''T. socranskii'' is 37 °C, but it will still slightly grow between 25 °C and 42 °C.
Morphology
''Treponema socranskii'' is
helically coiled and
motile
Motility is the ability of an organism to move independently, using metabolic energy.
Definitions
Motility, the ability of an organism to move independently, using metabolic energy, can be contrasted with sessility, the state of organisms th ...
using periplasmic
flagella
A flagellum (; ) is a hairlike appendage that protrudes from certain plant and animal sperm cells, and from a wide range of microorganisms to provide motility. Many protists with flagella are termed as flagellates.
A microorganism may have f ...
.
In liquid media, it can move
linearly
Linearity is the property of a mathematical relationship (''function'') that can be graphically represented as a straight line. Linearity is closely related to '' proportionality''. Examples in physics include rectilinear motion, the linear r ...
or in a twisting screw-like motion.
The cell size ranges from 6-15μm long and 0.16-0.18μm wide.
The cells are wider in the center than at the ends and are curved slightly.
When plated, colonies of ''T. socranskii'' form between 7–10 days after inoculation and appear white,
translucent
In the field of optics, transparency (also called pellucidity or diaphaneity) is the physical property of allowing light to pass through the material without appreciable scattering of light. On a macroscopic scale (one in which the dimensions a ...
, irregular, with a dense center.
Ecology
''Treponema socranskii'' is found in the space between the teeth and gums of patients with the varying forms of periodontitis.
Of the samples taken from across sampling sites of the gum line, ''T. socranskii'' is found to be one of the most abundant of its genus.
Studies on the human oral microbiome show that
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 ...
organisms including genera ''Treponema'', ''
Prevotella
''Prevotella'' is a genus of Gram-negative bacteria.
''Prevotella'' spp. are members of the oral, vaginal, and gut microbiota and are often recovered from anaerobic infections of the respiratory tract. These infections include aspiration pneum ...
'', ''
Selenomonas
Members of the genus ''Selenomonas'' (motile crescent-shaped bacteria in general) are referred to trivially as selenomonads. The genus ''Selenomonas'' constitutes a group of motile crescent-shaped bacteria and includes species living in the gast ...
'', ''Tannerella'', ''
Haemophilus
''Haemophilus'' is a genus of Gram-negative, pleomorphic, coccobacilli bacteria belonging to the family Pasteurellaceae. While ''Haemophilus'' bacteria are typically small coccobacilli, they are categorized as pleomorphic bacteria because of ...
'', and ''Catonella'' are not only present in samples from those with periodontitis, but they are actually
selected for and have a much higher
abundance
Abundance may refer to:
In science and technology
* Abundance (economics), the opposite of scarcities
* Abundance (ecology), the relative representation of a species in a community
* Abundance (programming language), a Forth-like computer prog ...
than healthy samples.
After treatment of periodontitis, there is a shift in the microbial community away from the Gram-negative organisms listed above, and selection for
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 bacte ...
organisms.
Healthy gumlines tend to be characterized by a low
diversity
Diversity, diversify, or diverse may refer to:
Business
*Diversity (business), the inclusion of people of different identities (ethnicity, gender, age) in the workforce
*Diversity marketing, marketing communication targeting diverse customers
* ...
of microorganisms within a single patient, but the
taxa
In biology, a taxon (back-formation from ''taxonomy''; plural taxa) is a group of one or more populations of an organism or organisms seen by taxonomists to form a unit. Although neither is required, a taxon is usually known by a particular nam ...
vary greatly across different individuals.
Individuals with periodontitis have a high diversity of microbes, but the
community structure
In the study of complex networks, a network is said to have community structure if the nodes of the network can be easily grouped into (potentially overlapping) sets of nodes such that each set of nodes is densely connected internally. In the part ...
is similar in all affected patients.
These trends are due to the anaerobic and
oligotroph
An oligotroph is an organism that can live in an environment that offers very low levels of nutrients. They may be contrasted with copiotrophs, which prefer nutritionally rich environments. Oligotrophs are characterized by slow growth, low rates of ...
ic conditions in the diseased gums causing the anaerobic bacteria to be able to out
compete
Competition is a rivalry where two or more parties strive for a common goal which cannot be shared: where one's gain is the other's loss (an example of which is a zero-sum game). Competition can arise between entities such as organisms, indivi ...
the aerobic copiotrophs that usually make up the healthy communities.
Metabolism
''Treponema socranskii'' differs from others in the genus due, in part, to its
metabolism
Metabolism (, from el, μεταβολή ''metabolē'', "change") is the set of life-sustaining chemical reactions in organisms. The three main functions of metabolism are: the conversion of the energy in food to energy available to run cell ...
.
''T. socranskii'' is able to ferment compounds that others are not able to do so.
The compounds that it can metabolize are
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 structurally ...
,
dextrin
Dextrins are a group of low-molecular-weight carbohydrates produced by the hydrolysis of starch and glycogen. Dextrins are mixtures of polymers of D-glucose units linked by α-(1→4) or α-(1→6) glycosidic bonds.
Dextrins can be produced from ...
,
fructose
Fructose, or fruit sugar, is a Ketose, ketonic monosaccharide, simple sugar found in many plants, where it is often bonded to glucose to form the disaccharide sucrose. It is one of the three dietary monosaccharides, along with glucose and galacto ...
,
galactose
Galactose (, '' galacto-'' + '' -ose'', "milk sugar"), sometimes abbreviated Gal, is a monosaccharide sugar that is about as sweet as glucose, and about 65% as sweet as sucrose. It is an aldohexose and a C-4 epimer of glucose. A galactose molec ...
,
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, using ...
,
glycogen
Glycogen is a multibranched polysaccharide of glucose that serves as a form of energy storage in animals, fungi, and bacteria. The polysaccharide structure represents the main storage form of glucose in the body.
Glycogen functions as one o ...
,
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 two- ...
,
mannose
Mannose is a sugar monomer of the aldohexose series of carbohydrates. It is a C-2 epimer of glucose. Mannose is important in human metabolism, especially in the glycosylation of certain proteins. Several congenital disorders of glycosylation ...
,
pectin
Pectin ( grc, πηκτικός ': "congealed" and "curdled") is a heteropolysaccharide, a structural acid contained in the primary lamella, in the middle lamella, and in the cell walls of terrestrial plants. The principal, chemical component of ...
,
raffinose
Raffinose is a trisaccharide composed of galactose, glucose, and fructose. It can be found in beans, cabbage, brussels sprouts, broccoli, asparagus, other vegetables, and whole grains. Raffinose can be hydrolyzed to D-galactose and sucrose by ...
,
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 most o ...
,
ribose
Ribose is a simple sugar and carbohydrate with molecular formula C5H10O5 and the linear-form composition H−(C=O)−(CHOH)4−H. The naturally-occurring form, , is a component of the ribonucleotides from which RNA is built, and so this compo ...
,
starch
Starch or amylum is a polymeric carbohydrate consisting of numerous glucose units joined by glycosidic bonds. This polysaccharide is produced by most green plants for energy storage. Worldwide, it is the most common carbohydrate in human diets ...
,
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 refined ...
,
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 ...
, 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 ...
.
The fermentation products are
acetic,
lactic, and
succinic acid
Succinic acid () is a dicarboxylic acid with the chemical formula (CH2)2(CO2H)2. The name derives from Latin ''succinum'', meaning amber. In living organisms, succinic acid takes the form of an anion, succinate, which has multiple biological ro ...
, with
formic acid
Formic acid (), systematically named methanoic acid, is the simplest carboxylic acid, and has the chemical formula HCOOH and structure . It is an important intermediate in chemical synthesis and occurs naturally, most notably in some ants. Es ...
as a minor product.
Genomics
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 ''T. socranskii'' was
sequenced
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 suc ...
by the
J. Craig Venter Institute (JCVI) using
Illumina sequencing Illumina dye sequencing is a technique used to determine the series of base pairs in DNA, also known as DNA sequencing. The reversible terminated chemistry concept was invented by Bruno Canard and Simon Sarfati at the Pasteur Institute in Paris. It ...
.
The genome contains 2,804,628
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 of which 2,547,778 are
coding pairs.
The
GC content
In molecular biology and genetics, GC-content (or guanine-cytosine content) is the percentage of nitrogenous bases in a DNA or RNA molecule that are either guanine (G) or cytosine (C). This measure indicates the proportion of G and C bases out o ...
is between 50-52 mol%.
The DNA also contains 2563 genes of which 2509 code for
protein
Proteins are large biomolecules and macromolecules that comprise one or more long chains of amino acid residues. Proteins perform a vast array of functions within organisms, including catalysing metabolic reactions, DNA replication, respo ...
s.
Implications
''Treponema socranskii'' and 11 other organisms show an increased growth rate that correlates with an increased GI (gingival index) score.
The GI score measures the intensity of the inflammation of the gingival crevice.
This correlation between growth and high GI scores, combined with the frequency of ''T. socranskii'' in the
gingival crevice
The gingival sulcus is an area of potential space between a tooth and the surrounding gingival tissue and is lined by sulcular epithelium. The depth of the sulcus (Latin for ''groove'') is bounded by two entities: apically by the gingival fi ...
of people with clinically-induced periodontitis and moderate/severe periodontitis has implications that point toward ''T. socranskii'' being a
causative agent
In biology, a pathogen ( el, πάθος, "suffering", "passion" and , "producer of") in the oldest and broadest sense, is any organism or agent that can produce disease. A pathogen may also be referred to as an infectious agent, or simply a germ ...
in periodontitis and gingivitis.
Periodontitis is the condition that arises after leaving gingivitis untreated.
In adults, periodontitis can be a major force in the acceleration of
tooth loss Tooth loss is a process in which one or more teeth come loose and fall out. Tooth loss is normal for deciduous teeth (baby teeth), when they are replaced by a person's adult teeth. Otherwise, losing teeth is undesirable and is the result of injur ...
because it damages the base of the teeth and harms their connection to the
skull
The skull is a bone protective cavity for the brain. The skull is composed of four types of bone i.e., cranial bones, facial bones, ear ossicles and hyoid bone. However two parts are more prominent: the cranium and the mandible. In humans, the ...
.
This condition is easily prevented by daily dental hygiene such as
brushing and
flossing
Dental floss is a cord of thin filaments used in interdental cleaning to remove food and dental plaque from between teeth or places a toothbrush has difficulty reaching or is unable to reach. Its regular use as part of oral cleaning is designed t ...
.
References
{{Taxonbar, from=Q24975387
socranskii
Bacteria described in 1984