Differential metabolism of Mycoplasma species as revealed by their genomes

The annotation and comparative analyses of the genomes of Mycoplasma synoviae and Mycoplasma hyopneumonie, as well as of other Mollicutes (a group of bacteria devoid of a rigid cell wall), has set the grounds for a global understanding of their metabolism and infection mechanisms. According to the annotation data, M. synoviae and M. hyopneumoniae are able to perform glycolytic metabolism, but do not possess the enzymatic machinery for citrate and glyoxylate cycles, gluconeogenesis and the pentose phosphate pathway. Both can synthesize ATP by lactic fermentation, but only M. synoviae can convert acetaldehyde to acetate. Also, our genome analysis revealed that M. synoviae and M. hyopneumoniae are not expected to synthesize polysaccharides, but they can take up a variety of carbohydrates via the phosphoenolpyruvate-dependent phosphotransferase system (PEP-PTS). Our data showed that these two organisms are unable to synthesize purine and pyrimidine de novo, since they only possess the sequences which encode salvage pathway enzymes. Comparative analyses of M. synoviae and M. hyopneumoniae with other Mollicutes have revealed differential genes in the former two genomes coding for enzymes that participate in carbohydrate, amino acid and nucleotide metabolism and host-pathogen interaction. The identification of these metabolic pathways will provide a better understanding of the biology and pathogenicity of these organisms.

Neutropenia na criança em quimioterapia / Neutropenia in children submitted to chemotherapy

Os autores fazem uma revisão bibliográfica com o objetivo de fornecer informações que orientem o manejo de pacientes pediátricos com neutropenia secundária à quimioterapia. A profilaxia de infecções e cuidados com a criança neutropênica febril são enfatizados

Manejo do paciente com anemia falciforme / Sickle cell anemia

Os autores pretendem com esse artigo fazer uma revisÝo bibliográfica, fornecendo dados a fim de auxiliar na orientaçÝo do manejo de pacientes portadores de anemia falciforme com suas manifestaçSes clínicas e complicaçSes