Pneumolysin is a

virulence factor Virulence factors (preferably known as pathogenicity factors or effectors in plant science) are cellular structures, molecules and regulatory systems that enable microbial pathogens ( bacteria, viruses, fungi, and protozoa) to achieve the followi ...

of the

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 ...

bacteria ''

Streptococcus pneumoniae ''Streptococcus pneumoniae'', or pneumococcus, is a Gram-positive, spherical bacteria, alpha-hemolytic (under aerobic conditions) or beta-hemolytic (under anaerobic conditions), aerotolerant anaerobic member of the genus Streptococcus. They are ...

''. It is a pore-forming toxin of 53 kDa composed of 471

amino acids Amino acids are organic compounds that contain both amino and carboxylic acid functional groups. Although hundreds of amino acids exist in nature, by far the most important are the alpha-amino acids, which comprise proteins. Only 22 alpha am ...

. It has a range of

biological activity In pharmacology, biological activity or pharmacological activity describes the beneficial or adverse effects of a drug on living matter. When a drug is a complex chemical mixture, this activity is exerted by the substance's active ingredient or p ...

, including the ability to

lyse Lyse may refer to: * Lyse Abbey, a former Cistercian abbey in Norway * Lyse, an alternative name of Lysebotn, Norway * Lyse Energi, a Norwegian power company * Łyse, Masovian Voivodeship, a village in east-central Poland * Łyse, Podlaskie Voi ...

and interfere with the function of cells and soluble molecules of the immune system. Released pneumolysin will aid the bacteria during colonization by facilitating adherence to the host, during invasion by damaging host cells, and during infection by interfering with the host immune response. The presence of pneumolysin in

sputum Sputum is mucus that is coughed up from the lower airways (the trachea and bronchi). In medicine, sputum samples are usually used for a naked eye examination, microbiological investigation of respiratory infections and cytological investigation ...

urine Urine is a liquid by-product of metabolism in humans and in many other animals. Urine flows from the kidneys through the ureters to the urinary bladder. Urination results in urine being excreted from the body through the urethra. Cellular m ...

CSF CSF may refer to: Biology and medicine * Cerebrospinal fluid, clear colorless bodily fluid found in the brain and spine * Colony-stimulating factor, secreted glycoproteins * Cancer slope factor, estimate the risk of cancer * Classical swine fev ...

and blood can be indicative of an ''S. pneumoniae'' infection.

References

External links

World Pneumonia Day
{{pore-forming toxins Bacterial toxins