Gemella

A genus of motile, aerobic, facultatively anaerobic, coccoid bacteria (family Streptococcaceae) that occur singly or in pairs, with flattened adjacent sides. They are Gram-indeterminate but have a cell wall like that of Gram-positive bacteria, and are parasitic on mammals. The type species is G. haemolysans, which is found in bronchial secretions and in mucus from the respiratory tract. [L. dim. of geminus, twin]

- G. morbillorum a microaerophilic bacterium, formerly called Streptococcus morbillorum, that fails to produce β-hemolysis of blood agar and lacks distinguishing serogroup antigens; causes serious infections in some patients similar to those seen with viridans streptococci.

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Ge·mel·la (jə-melґə) [L., dim. of gemellus a twin] a genus of gram-positive, aerobic or facultatively anaerobic cocci of the family Staphylococcaceae, occurring singly or in pairs, tetrads, or short chains, with adjacent sides flattened. Organisms are part of the normal oropharyngeal, gastrointestinal, and urogenital flora of many different animals but can also cause infectious illnesses, particularly in immunocompromised persons. The type species is G. haemolyґsans.