Article

Classification of coryneform bacteria associated with human urinary tract infection (group D2) as Corynebacterium urealyticum sp. nov.

National Collection of Type Cultures, Central Public Health Laboratory, London, United Kingdom.
International journal of systematic bacteriology (Impact Factor: 2.27). 02/1992; 42(1):178-81. DOI: 10.1099/00207713-42-1-178
Source: PubMed

ABSTRACT Urealytic strains of coryneform bacteria that are designated Corynebacterium group D2 and are isolated from human urine are a cause of urinary tract infections. Cell wall and lipid analyses confirmed that these organisms are members of the genus Corynebacterium but can be separated from other species in the genus on the basis of DNA base composition and DNA-DNA hybridization values. Biochemically, strains in this taxon can be distinguished from other Corynebacterium spp. by their failure to produce acid from carbohydrates, by their failure to reduce nitrates, and by their ability to hydrolyze urea. We regard these bacteria as a new species of the genus Corynebacterium and propose the name Corynebacterium urealyticum. The type strain is strain NCTC 12011 (= ATCC 43042).

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Available from: Pedro Luis Valero-Guillén, Jan 28, 2015
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    ABSTRACT: Departamento de Microbiología Médica. Fundación Jiménez Díaz. Madrid. Hace 30 años el género Corynebacterium incluía prácticamente sólo a Corynebacterium diphtheriae, hecho que se justificaba por la gravedad de la enfermedad que produce y por las consecuencias epidemiológicas bien conocidas. Los organismos morfológicamente similares a C. diphtheriae fueron denominados corineformes o difteromorfos y su principal interés estribaba en poder diferenciarlos del agente responsable de la difteria. A partir de la década de los setenta se empieza a describir infecciones por difteromorfos, al mismo tiempo que se profundiza en la caracterización taxonómica de muchos de estos microorganismos. En la actualidad, el género Corynebacterium contiene cerca de 50 especies diferentes, la mitad de las cuales han sido implicadas en infecciones humanas. Corynebacterium urealyticum empezó a dar señales de su existencia en la década de los cuarenta, pero no fue hasta 1985 cuando empezó a estudiarse con detenimiento. Una serie de estudios, realizados mayoritariamente en España, permitieron no sólo caracterizar a este organismo sino definir su patogenicidad, espectro clínico de la infección, epidemiología, sensibilidad antibiótica y tratamiento. Denominado inicialmente corineforme del grupo D2 del CDC su estudio taxonómico demostró que, efectivamente, se trataba de un organismo perteneciente al género Corynebacterium y diferente de los hasta entonces conocidos, siendo denominado C. urealyticum. Esta especie contiene ácido meso-diaminopimélico, arabinosa y galactosa en su pared. La composición en ácidos grasos es la típica del género Corynebacterium, siendo la mayoría de cadena corta, monoinsaturados y conteniendo trazas de ácido tuberculosteárico. Contienen ácidos corinemicólicos de 26 a 36 átomos de carbono y la menaquinona más importante es la MK-9 (H 2). Su cociente G+C es de 61-62 moles %. Mediante hibridación DNA-DNA con otras especies del género la totalidad de las cepas de C. urealyticum estudiadas están muy próximas entre sí, constituyendo un grupo homogéneo y diferente del resto de las especies conocidas. Esta homogeneidad de la especie ha permitido, utilizando diferentes sistemas de ribotipia, agrupar cepas de diferente origen geográfico y procedencia (humana o animal) en 8 o 12 clusters.