RESUMO
Purple bacteria are extensively used in bacterial photosynthesis research. This review describes the structure of light-harvesting I, light-harvesting II and reaction center of photosynthetic apparatus of pur- ple bacteria and discusses the regulation mechanisms of photosynthesis (PS) gene transcription, with an emphasis laid on the transcriptional regulation of PS gene by PpsR/AppA system.
RESUMO
Antimicrobial peptides, a cluster of small peptides secreted by the majority of creatures, have been demonstrated with activity against a wide range of microorganisms including bacteria, protozoa, yeast, fungi, viruses and even tumor cells. These peptides have some features such as broad spectrum , high effi-cacy and stability, little drug resistance. A lack of new antibiotics combined with emerging multi-drug resis-tance issues demands that new antimicrobial strategies be explored for treating these infections. It has been proposed that the antimicrobial peptides might form the foundation for a new class of clinically useful an-timicrobials. We review the advantages of these molecules in construction features and bioactivity, with the focus on the mechanism and clinical applications.