Assuntos
Infecções Oculares Fúngicas/diagnóstico , Ceratite/diagnóstico , Pythium/isolamento & purificação , Análise de Sequência de DNA , Adulto , Infecções Oculares Fúngicas/etiologia , Infecções Oculares Fúngicas/cirurgia , Humanos , Ceratite/etiologia , Ceratite/cirurgia , Ceratoplastia Penetrante , Masculino , Pythium/patogenicidade , Resultado do TratamentoRESUMO
Phylogenetic relationships among 50 Phytophthora species and between Phytophthora and other oomycetes were examined on the basis of the ITS sequences of genomic rDNA. Phytophthora grouped with Pythium, Peronospora, and Halophytophthora, distant from genera in the Saprolegniales. Albugo was intermediate between these two groups. Unlike Pythium, Phytophthora was essentially monophyletic, all but three species forming a cluster of eight clades. Two clades contained only species with nonpapillate sporangia. The other six clades included either papillate and semipapillate, or semipapillate and nonpapillate types, transcending traditional morphological groupings, which are evidently not natural assemblages. Peronospora was related to P. megakarya and P. palmivora and appears to be derived from a Phytophthora that has both lost the ability to produce zoospores and become an obligate biotroph. Three other Phytophthoras located some distance from the main Phytophthora-Peronospora cluster probably represent one or more additional genera.
Assuntos
DNA Espaçador Ribossômico/genética , Oomicetos/genética , Filogenia , Phytophthora/genética , DNA Fúngico/genética , Evolução Molecular , Dados de Sequência Molecular , Oomicetos/classificação , Phytophthora/classificação , Doenças das Plantas/microbiologia , Reação em Cadeia da Polimerase/métodos , Análise de Sequência de DNARESUMO
The 60-kDa cysteine-rich outer membrane protein gene (omp 2) from nine Chlamydia pneumoniae isolates (TW-183, CM-1, CWL-050, CWL-011, IOL-207, FIL, Kajaani-6, Helsinki-12, and Parjaanonen) was amplified by PCR and sequenced from positions 1 to 580. In contrast to the sequence differences previously observed in this gene in other chlamydial species, all nine C. pneumoniae isolates were 100% identical. However, when sera from C. pneumoniae microimmunofluorescence-positive patients (with clinical signs of persistent cough or asthma) were immunoblotted against five C. pneumoniae isolates, distinct antigenic differences were observed. TW-183 was characterized by major bands at 35 and 43 kDa. In contrast, the other four isolates tested produced similar, though not identical, immunoblot profiles, characterized by strong bands at 18, 25, 29, 40, 46, and 53 kDa. These data support the fact that significant differences do exist between C. pneumoniae isolates, but unlike the case with other chlamydial species, these differences do not reside in either of the commonly studied outer membrane protein genes, omp 1 or omp 2.