[citation needed] Bacteria of the genus Acinetobacter are known to form intracellular inclusions of polyhydroxyalkanoates under certain environmental conditions (e.g. lack of elements such as phosphorus, nitrogen, or oxygen combined with an excessive supply of carbon sources).
[citation needed] Acinetobacter is a compound word from scientific Greek [α + κίνητο + βακτηρ(ία)], meaning nonmotile rod.
[citation needed] Because routine identification in the clinical microbiology laboratory is not yet possible, Acinetobacter isolates are divided and grouped into three main complexes:[citation needed] Different species of bacteria in this genus can be identified using fluorescence-lactose-denitrification to find the amount of acid produced by metabolism of glucose.
[11] Acinetobacter is frequently isolated in nosocomial infections, and is especially prevalent in intensive care units, where both sporadic cases and epidemic and endemic occurrences are common.
[12] In particular, A. baumannii is frequently isolated as the cause of hospital-acquired pneumonia among patients admitted to the intensive care unit.
In most cases of ventilator-associated pneumonia, the equipment used for artificial ventilation such as endotracheal tubes or bronchoscopes serve as the source of infection and result in the colonization of the lower respiratory tract by A. baumannii.
[13] Case reports also link A. baumannii to endocarditis, keratitis, peritonitis, and very rarely fatal neonatal sepsis.
[15][16] A. baumannii can survive on the human skin or dry surfaces for weeks and is resistant to a variety of disinfectants, making it particularly easy to spread in a hospital setting.
A dramatic increase in antibiotic resistance in Acinetobacter strains has been reported by the Centers for Disease Control and Prevention (CDC), and the carbapenems are recognised as the gold-standard and treatment of last resort.
[21] Recently sulbactam-durlobactam, a new antibacterial combination undergoing phase 3 trial, has demonstrated good in vitro activity also against carbapenem-resistant A. baumannii isolates (92% susceptibility).
Among one set of isolates from Walter Reed Army Medical Center, 13 (35%) were susceptible to imipenem only, and two (4%) were resistant to all drugs tested.
[30] Bacterial transformation involves the transfer of DNA from a donor to a recipient bacterium through the intervening liquid medium.
Recipient bacteria must first enter a special physiological state termed competence to receive donor DNA.
A. calcoaceticus is induced to become competent for natural transformation by dilution of a stationary culture into fresh nutrient medium.