''Haemophilus parainfluenzae'' is a species of''

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 t ...

''. It is one of the HACEK organisms. ''H. parainfluenzae'' is an opportunistic pathogen that has been associated with

endocarditis Endocarditis is an inflammation of the inner layer of the heart, the endocardium. It usually involves the heart valves. Other structures that may be involved include the interventricular septum, the chordae tendineae, the mural endocardium, or the ...

bronchitis Bronchitis is inflammation of the bronchi (large and medium-sized airways) in the lungs that causes coughing. Bronchitis usually begins as an infection in the nose, ears, throat, or sinuses. The infection then makes its way down to the bronchi. ...

, otitis,

conjunctivitis Conjunctivitis, also known as pink eye, is inflammation of the outermost layer of the white part of the eye and the inner surface of the eyelid. It makes the eye appear pink or reddish. Pain, burning, scratchiness, or itchiness may occur. The ...

pneumonia Pneumonia is an inflammatory condition of the lung primarily affecting the small air sacs known as alveoli. Symptoms typically include some combination of productive or dry cough, chest pain, fever, and difficulty breathing. The severi ...

abscesses An abscess is a collection of pus that has built up within the tissue of the body. Signs and symptoms of abscesses include redness, pain, warmth, and swelling. The swelling may feel fluid-filled when pressed. The area of redness often extends ...

and genital tract infections.

Natural genetic transformation

''H. parainfluenzae'' biotypes I and II are capable of natural genetic transformation. Natural genetic transformation is a bacterial adaptation for DNA transfer. In order for a bacterium to bind, take up and recombine exogenous DNA into its

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 g ...

it must enter a special physiological state termed

natural competence In microbiology, genetics, cell biology, and molecular biology, competence is the ability of a cell to alter its genetics by taking up extracellular ("naked") DNA from its environment in the process called transformation. Competence may be diff ...

. In ''H. parainfluenzae'', competence is induced during the late stationary phase of growth. Natural DNA transformation may play a major role in the exchange of genetic information among ''H. parainfluenzae'' isolates.

References

External links

*
Type strain of ''Haemophilus parainfluenzae'' at Bac''Dive'' - the Bacterial Diversity Metadatabase
parainfluenzae Bacteria described in 1922 {{gammaproteobacteria-stub