ABSTRACT
The sequencing of the complete genome of Anaplasma marginale has enabled the identification of several genes that encode membrane proteins, thereby increasing the chances of identifying candidate immunogens. Little is known regarding the genetic variability of genes that encode membrane proteins in A. marginale isolates. The aim of the present study was to determine the degree of conservation of the predicted amino acid sequences of OMP1, OMP4, OMP5, OMP7, OMP8, OMP10, OMP14, OMP15, SODb, OPAG1, OPAG3, VirB3, VirB9-1, PepA, EF-Tu and AM854 proteins in a Brazilian isolate of A. marginale compared to other isolates. Hence, primers were used to amplify these genes: omp1, omp4, omp5, omp7, omp8, omp10, omp14, omp15, sodb, opag1, opag3, virb3, VirB9-1, pepA, ef-tu and am854. After polimerase chain reaction amplification, the products were cloned and sequenced using the Sanger method and the predicted amino acid sequence were multi-aligned using the CLUSTALW and MEGA 4 programs, comparing the predicted sequences between the Brazilian, Saint Maries, Florida and A. marginale centrale isolates. With the exception of outer membrane protein (OMP) 7, all proteins exhibited 92-100 percent homology to the other A. marginale isolates. However, only OMP1, OMP5, EF-Tu, VirB3, SODb and VirB9-1 were selected as potential immunogens capable of promoting cross-protection between isolates due to the high degree of homology (over 72 percent) also found with A. (centrale) marginale.
Subject(s)
Animals , Cattle , Anaplasma marginale , Bacterial Outer Membrane Proteins , Genetic Variation , Amino Acid Sequence , Anaplasma marginale , Brazil , Molecular Sequence Data , Polymerase Chain ReactionABSTRACT
O objetivo de nosso estudo foi realizar tipagem molecular de 25 amostras clínicas de Candida spp, isoladas de crianças com candidemia, internadas na unidade de terapia intensiva neonatal de um Hospital Universitário entre 1998 a 2006. Dados demográficos e clínicos foram obtidos de prontuários para conhecimento dos aspectos clínicos e epidemiológicos. Identificação das leveduras foi feita por método convencional e a susceptibilidade antifúngica por método de microdiluição. O perfil genético foi determinado pela técnica de RAPD-PCR. Candida albicans (11; 44 por cento) e Candida parapsilosis (10; 40 por cento) foram as mais isoladas. Dezessete (68 por cento) dos recém-nascidos tinham peso inferior a 1.500g. Prematuridade (92 por cento), uso de cateter venoso central (100 por cento), foram as condições de risco mais associados. Dezenove (76 por cento) pacientes foram a óbito. Apenas uma cepa de Candida parapsilosis, mostrou ser sensível dose dependente ao fluconazol. Na análise molecular, foram observados 11 padrões genéticos distintos. Somente em dois casos foi observada relação epidemiológica, sugerindo mesma fonte de infecção.
The aim of our study was to perform molecular typing on 25 clinical samples of Candida spp that were isolated from children with candidemia who were hospitalized in the neonatal intensive care unit of a university hospital between 1998 and 2006. Demographic and clinical data were obtained from the medical records to ascertain the clinical and epidemiological characteristics. Yeast identification was done using conventional methods and susceptibility to antifungals was assessed using a microdilution method. The genetic profile was determined using the RAPD-PCR technique. Candida albicans (11; 44 percent) and Candida parapsilosis (10; 40 percent) were the species most frequently isolated. Seventeen (68 percent) of the newborns weighed less than 1,500g. Prematurity (92 percent) and use of a central venous catheter (100 percent) were the risk conditions with greatest association. Nineteen patients (76 percent) died. Only one strain of Candida parapsilosis showed dose-dependent sensitivity to fluconazole. Molecular analysis showed 11 distinct genetic patterns. An epidemiological relationship was seen in only two cases, thus suggesting the same source of infection.