Spectinomycin, sold under the tradename Trobicin among others, is an

antibiotic An antibiotic is a type of antimicrobial substance active against bacteria. It is the most important type of antibacterial agent for fighting bacterial infections, and antibiotic medications are widely used in the treatment and prevention ...

useful for the treatment of

gonorrhea infection Gonorrhea, colloquially known as the clap, is a sexually transmitted infection (STI) caused by the bacterium ''Neisseria gonorrhoeae''. Infection may involve the genitals, mouth, or rectum. Infected men may experience pain or burning with ur ...

s. It is given by injection into a muscle. Common side effects include pain at the area of injection, rash, nausea, fever, and trouble sleeping. Severe

allergic reaction Allergies, also known as allergic diseases, refer a number of conditions caused by the hypersensitivity of the immune system to typically harmless substances in the environment. These diseases include hay fever, food allergies, atopic dermati ...

s may occasionally occur. It is generally safe to use during pregnancy. It may be used by those who are allergic to

penicillin Penicillins (P, PCN or PEN) are a group of β-lactam antibiotics originally obtained from ''Penicillium'' moulds, principally '' P. chrysogenum'' and '' P. rubens''. Most penicillins in clinical use are synthesised by P. chrysogenum usin ...

cephalosporin The cephalosporins (sg. ) are a class of β-lactam antibiotics originally derived from the fungus '' Acremonium'', which was previously known as ''Cephalosporium''. Together with cephamycins, they constitute a subgroup of β-lactam antibiotic ...

s. It is in the aminocyclitol class of drugs and works by stopping the making of protein by certain bacteria. Spectinomycin was discovered in 1961. It is on the

World Health Organization's List of Essential Medicines The WHO Model List of Essential Medicines (aka Essential Medicines List or EML), published by the World Health Organization (WHO), contains the medications considered to be most effective and safe to meet the most important needs in a health s ...

. It is not available in the United States for human use. It is made from the

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 amon ...

'' Streptomyces spectabilis''.

Medical uses

It is given by

intramuscular injection Intramuscular injection, often abbreviated IM, is the injection of a substance into a muscle. In medicine, it is one of several methods for parenteral administration of medications. Intramuscular injection may be preferred because muscles have ...

to treat

gonorrhea Gonorrhea, colloquially known as the clap, is a sexually transmitted infection (STI) caused by the bacterium ''Neisseria gonorrhoeae''. Infection may involve the genitals, mouth, or rectum. Infected men may experience pain or burning with ur ...

, especially in patients who are allergic to

s. This antibiotic is no longer available in the United States for human use, but is still available for veterinary use.

Side effects

Side effects include

itching Itch (also known as pruritus) is a sensation that causes the desire or reflex to scratch. Itch has resisted many attempts to be classified as any one type of sensory experience. Itch has many similarities to pain, and while both are unpleasant ...

chills Chills is a feeling of coldness occurring during a high fever, but sometimes is also a common symptom which occurs alone in specific people. It occurs during fever due to the release of cytokines and prostaglandins as part of the inflammatory r ...

, stomach ache, and red rash.

Mechanism of action

Spectinomycin binds to the 30S subunit of the bacterial

ribosome Ribosomes ( ) are macromolecular machines, found within all cells, that perform biological protein synthesis (mRNA translation). Ribosomes link amino acids together in the order specified by the codons of messenger RNA (mRNA) molecules to fo ...

and interrupts protein synthesis. One form of resistance has emerged in the

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 rR ...

in '' Pasteurella multocida''.

Biosynthetic mechanism

Biosynthesis of spectinomycin begins similar to all aminoglycosides, with the formation of an inositol ring. The difference is the initial modification that forms the inositol ring of spectinomycin. The process begins with a

glucose-6-phosphate Glucose 6-phosphate (G6P, sometimes called the Robison ester) is a glucose sugar phosphorylated at the hydroxy group on carbon 6. This dianion is very common in cells as the majority of glucose entering a cell will become phosphorylated in this wa ...

(1a), which is oxidized by NAD⁺ to form a

ketone In organic chemistry, a ketone is a functional group with the structure R–C(=O)–R', where R and R' can be a variety of carbon-containing substituents. Ketones contain a carbonyl group –C(=O)– (which contains a carbon-oxygen double bon ...

at C2 (2a). This ketone is then formed into a primary

amine In chemistry, amines (, ) are compounds and functional groups that contain a basic nitrogen atom with a lone pair. Amines are formally derivatives of ammonia (), wherein one or more hydrogen atoms have been replaced by a substituent such ...

group through

pyridoxal phosphate Pyridoxal phosphate (PLP, pyridoxal 5'-phosphate, P5P), the active form of vitamin B6, is a coenzyme in a variety of enzymatic reactions. The International Union of Biochemistry and Molecular Biology has catalogued more than 140 PLP-dependent ...

(PLP) and glutamine transamination (3a). This process is repeated again at C4 to form a second primary amine (4a). Once these two amines are present, the glucose ring is ready to be methylated through two

S-adenosyl methionine ''S''-Adenosyl methionine (SAM), also known under the commercial names of SAMe, SAM-e, or AdoMet, is a common cosubstrate involved in methyl group transfers, transsulfuration, and aminopropylation. Although these anabolic reactions occur throug ...

molecules (5a). With this methylation, the glucose ring is finally ready to be converted into an inositol ring through inositol cyclase (6a). This can then be hydrolyzed to get rid of the phosphate group, making the inositol ring necessary for spectinomycin (7a). While all this happens, an alternate pathway is occurring creating the sugar functional group from a similar starting product. In this pathway,

glucose-1-phosphate Glucose 1-phosphate (also called cori ester) is a glucose molecule with a phosphate group on the 1'-carbon. It can exist in either the α- or β- anomeric form. Reactions of α-glucose 1-phosphate Catabolic In glycogenolysis, it is the direct pr ...

is used as the starting product (1b). This is converted into a

TDP-glucose Thymidine diphosphate glucose (often abbreviated dTDP-glucose or TDP-glucose) is a nucleotide-linked sugar consisting of deoxythymidine diphosphate linked to glucose. It is the starting compound for the syntheses of many deoxysugars. Biosynthes ...

through TDP synthase (2b). TDP glucose then has the hydroxyl removed from C6 through a hydratase enzyme (3b), which is then reduced through NADH at C4 creating a new product (4b). With this ketone present, PLP and glutamine can come in to convert it to a primary amine (5b) which can then be removed through a deaminase (6b). This conversion to 6b is also accompanied by a double reduction at C4 and C3 through two more NADH molecules, giving the final product necessary to form the aminoglycoside. With this, products 7a and 6b can come together, removing the TDP functional group and combining with the sugar molecule to form the aminoglycoside spectinomycin.

Nature

It is in aminocyclitol class, closely related to the

aminoglycosides Aminoglycoside is a medicinal and bacteriologic category of traditional Gram-negative antibacterial medications that inhibit protein synthesis and contain as a portion of the molecule an amino-modified glycoside (sugar). The term can also refer ...

. Spectinomycin is industrially produced by fermentation of the

'' Streptomyces spectabilis''. Spectinomycin is produced in nature by many organisms including cyanobacteria and various plant species. It is present in 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 ...

or plastome of many plastids as the spc

operon In genetics, an operon is a functioning unit of DNA containing a cluster of genes under the control of a single promoter. The genes are transcribed together into an mRNA strand and either translated together in the cytoplasm, or undergo spli ...

, which is usually two to 10 genes long. The difference in size may be due to the elimination of obsolete genes or the takeover of its function by nuclear genes. Spectinomycin is mainly produced by organisms as a

defence mechanism In psychoanalytic theory, a defence mechanism (American English: defense mechanism), is an unconscious psychological operation that functions to protect a person from anxiety-producing thoughts and feelings related to internal conflicts and ...

against predators.

History

Spectinomycin was discovered 1961. A disruption in the supply occurred in 2001.

References

External links

* {{portal bar, Medicine Antibiotics World Health Organization essential medicines 4-Pyrones Wikipedia medicine articles ready to translate