''Lactobacillus crispatus'' is a common, rod-shaped species of

genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of living and fossil organisms as well as viruses. In the hierarchy of biological classification, genus comes above species and below family. In binomial nom ...

Lactobacillus ''Lactobacillus'' is a genus of Gram-positive, aerotolerant anaerobes or microaerophilic, rod-shaped, non-spore-forming bacteria. Until 2020, the genus ''Lactobacillus'' comprised over 260 phylogenetically, ecologically, and metabolically div ...

'' and is a

hydrogen peroxide Hydrogen peroxide is a chemical compound with the formula . In its pure form, it is a very pale blue liquid that is slightly more viscous than water. It is used as an oxidizer, bleaching agent, and antiseptic, usually as a dilute solution (3%� ...

(H₂O₂) producing beneficial microbiota species located in both the vagina, through

vaginal discharge Vaginal discharge is a mixture of liquid, cells, and bacteria that lubricate and protect the vagina. This mixture is constantly produced by the cells of the vagina and cervix, and it exits the body through the vaginal opening. The composition, amou ...

, and the vertebrate

gastrointestinal The gastrointestinal tract (GI tract, digestive tract, alimentary canal) is the tract or passageway of the digestive system that leads from the mouth to the anus. The GI tract contains all the major organs of the digestive system, in humans and ...

tract. The strain CTV-05 is used as a

probiotic Probiotics are live microorganisms promoted with claims that they provide health benefits when consumed, generally by improving or restoring the gut microbiota. Probiotics are considered generally safe to consume, but may cause bacteria- host ...

that can be used by

premenopausal Menopause, also known as the climacteric, is the time in women's lives when menstrual periods stop permanently, and they are no longer able to bear children. Menopause usually occurs between the age of 47 and 54. Medical professionals often d ...

and

postmenopausal Menopause, also known as the climacteric, is the time in women's lives when menstrual periods stop permanently, and they are no longer able to bear children. Menopause usually occurs between the age of 47 and 54. Medical professionals often d ...

women that experience recurrent

urinary tract infections A urinary tract infection (UTI) is an infection that affects part of the urinary tract. When it affects the lower urinary tract it is known as a bladder infection (cystitis) and when it affects the upper urinary tract it is known as a kidne ...

. It is being evaluated specifically for the prevention and treatment of

bacterial vaginosis Bacterial vaginosis (BV) is a disease of the vagina caused by excessive growth of bacteria. Common symptoms include increased vaginal discharge that often smells like fish. The discharge is usually white or gray in color. Burning with urination ...

, which is characterized by the absence of ''Lactobacillus'' flora necessary to protect the host from infection.

History

The species name derives from

Latin Latin (, or , ) is a classical language belonging to the Italic branch of the Indo-European languages. Latin was originally a dialect spoken in the lower Tiber area (then known as Latium) around present-day Rome, but through the power of the ...

, meaning "curled", referring to the shape of the bacteria. ''L. crispatus'' was first isolated in 1953 by Brygoo and Aladame, who proposed it as a new species of the genus ''

Eubacterium ''Eubacterium'' is a genus of Gram-positive bacteria in the family Eubacteriaceae. These bacteria are characterised by a rigid cell wall. They may either be motile or nonmotile. If motile, they have a flagellum A flagellum (; ) is a hair ...

''. In the 1970s the type strain VPI 3199 (ATCC 33820) of ''L. crispatus'' (at the time still designated "''Eubacterium crispatum''") was deposited in the collection of the Anaerobe Laboratory,

Virginia Polytechnic Institute and State University Virginia Tech (formally the Virginia Polytechnic Institute and State University and informally VT, or VPI) is a public land-grant research university with its main campus in Blacksburg, Virginia. It also has educational facilities in six regi ...

(VPI), where it was identified as a ''Lactobacillus'' and characterized by Moore and Holdeman. Addressing the problem of genetic heterogeneity among a vast number of strains identified as '' L. acidophilus'' based on phenotypic similarity, Johnson et al. performed DNA homology experiments on 89 previously proposed ''L. acidophilus'' strains and delineated six distinct homology groups. Only the strains pertaining to DNA homology group A1 were still designated ''L. acidophilus''. Strains in the homology groups A2, A3, A4, B1 and B2 were proposed to be distinct species and later reclassified as ''L. crispatus'', '' L. amylovorus'', '' L. gallinarum'', '' L. gasseri'' and '' L. johnsonii'' respectively. In the case of ''L. crispatus'' this happened in 1983 as Cato and her coworkers recharacterized strain VPI 3199 and discovered 100% DNA homology with VPI 7635 (ATCC 33197), the type strain of "''L. acidophilus''" group A2.

Taxonomy

It is a species in the phylum

Bacillota The Bacillota (synonym Firmicutes) are a phylum of bacteria, most of which have gram-positive cell wall structure. The renaming of phyla such as Firmicutes in 2021 remains controversial among microbiologists, many of whom continue to use the earl ...

, in the

class Class or The Class may refer to: Common uses not otherwise categorized * Class (biology), a taxonomic rank * Class (knowledge representation), a collection of individuals or objects * Class (philosophy), an analytical concept used differentl ...

Bacilli Bacilli is a taxonomic class of bacteria that includes two orders, Bacillales and Lactobacillales, which contain several well-known pathogens such as ''Bacillus anthracis'' (the cause of anthrax). ''Bacilli'' are almost exclusively gram-positi ...

, in the order

Lactobacillales Lactobacillales are an order of gram-positive, low-GC, acid-tolerant, generally nonsporulating, nonrespiring, either rod-shaped (bacilli) or spherical (cocci) bacteria that share common metabolic and physiological characteristics. These bact ...

, in the family

Lactobacillaceae The ''Lactobacillaceae'' are a family of lactic acid bacteria. It is the only family in the lactic acid bacteria which includes homofermentative and heterofermentative organisms; in the ''Lactobacillaceae,'' the pathway used for hexose fermentati ...

and the

''. It is one of 122 other species identified within the genus.

Genome

Even within ''L. crispatus'' there is substantial genetic variation: strains of ''L. crispatus'' have genome sizes ranging from 1.83 to 2.7 Mb, and encode 1,839 (EM-LC1) to 2,688 (FB077-07)

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, res ...

s. The genome of ''Lactobacillus crispatus'' strain ST1, which colonizes chicken, consists of about 2,043,161

nucleotides Nucleotides are organic molecules consisting of a nucleoside and a phosphate. They serve as monomeric units of the nucleic acid polymers – deoxyribonucleic acid (DNA) and ribonucleic acid (RNA), both of which are essential biomolecules with ...

and encodes 2,024 proteins, 76

RNA Ribonucleic acid (RNA) is a polymeric molecule essential in various biological roles in coding, decoding, regulation and expression of genes. RNA and deoxyribonucleic acid ( DNA) are nucleic acids. Along with lipids, proteins, and carbohydra ...

genes and has a circular chromosomal shape.

Ecology

The strain of ''Lactobacillus crispastus'' was originally isolated from a pouch in a chicken

gullet The esophagus (American English) or oesophagus (British English; both ), non-technically known also as the food pipe or gullet, is an organ in vertebrates through which food passes, aided by peristaltic contractions, from the pharynx to the ...

and is considered to be one of the strongest H₂O₂-producing lactobacilli. Like many other ''Lactobacillus'' species, it can be severely altered by changes to the immune system, hormone levels and from the use of

antimicrobials An antimicrobial is an agent that kills microorganisms or stops their growth. Antimicrobial medicines can be grouped according to the microorganisms they act primarily against. For example, antibiotics are used against bacteria, and antifungals a ...

. ''Lactobacillus crispatus'' is a normal

inhabitant Domicile is relevant to an individual's "personal law," which includes the law that governs a person's status and their property. It is independent of a person's nationality. Although a domicile may change from time to time, a person has only one ...

of the lower reproductive tract in healthy women.

Probiotic use

CTV-05 gelatin

suppository A suppository is a dosage form used to deliver medications by insertion into a body orifice where it dissolves or melts to exert local or systemic effects. There are three types of suppositories, each to insert into a different sections: rectal ...

capsules (LACTIN-V) are inserted into the vagina as a probiotic that can help maintain healthy flora. Studies have shown that ''L. crispastus'' CTV-05 effectively colonized the vagina and helped prevent and treat recurrent bacterial vaginosis and other

genital A sex organ (or reproductive organ) is any part of an animal or plant that is involved in sexual reproduction. The reproductive organs together constitute the reproductive system. In animals, the testis in the male, and the ovary in the female, a ...

infections. Scientists have stated that evidence from clinical trials suggests that these probiotics will safely and effectively treat bacterial vaginosis if used alone or alongside an antibiotic treatment if an infection had already arisen. Condom use has showed increased colonization of ''Lactobacillus crispatus'' in the vagina because it protects against both bacterial

vaginosis Bacterial vaginosis (BV) is a disease of the vagina caused by excessive growth of bacteria. Common symptoms include increased vaginal discharge that often smells like fish. The discharge is usually white or gray in color. Burning with urination ...

(BV) and

human immunodeficiency virus The human immunodeficiency viruses (HIV) are two species of ''Lentivirus'' (a subgroup of retrovirus) that infect humans. Over time, they cause acquired immunodeficiency syndrome (AIDS), a condition in which progressive failure of the immun ...

(HIV).

References

External links

Type strain of ''Lactobacillus crispatus'' at Bac''Dive'' - the Bacterial Diversity Metadatabase
*https://www.micropia.nl/en/discover/news/2019/5/27/A-healthy-vagina-with-Lactobacillus-crispatus-bacteria/ {{Taxonbar, from=Q2355641 Lactobacillaceae Probiotics