Investigação
| 100-1 | The use of proteomics to study host-Paracoccidioides brasiliensis interactions㰀⼀戀㸀㰀⼀琀搀㸀㰀⼀琀爀㸀㰀琀爀㸀㰀琀搀 瘀愀氀椀最渀㴀琀漀瀀㸀䄀甀琀栀漀爀猀㨀㰀⼀琀搀㸀㰀琀搀㸀㰀甀㸀䌀攀氀椀愀 䴀愀爀椀愀 搀攀 䄀氀洀攀椀搀愀 匀漀愀爀攀猀 匀漀愀爀攀猀 㰀⼀甀㸀 ⠀唀䘀䜀 ⴀ 唀渀椀瘀攀爀猀椀搀愀搀攀 䘀攀搀攀爀愀氀 搀攀 䜀漀椀愀猀⤀ 㰀⼀琀搀㸀㰀⼀琀爀㸀㰀⼀琀愀戀氀攀㸀㰀瀀 愀氀椀最渀㴀樀甀猀琀椀昀礀㸀㰀戀㸀㰀昀漀渀琀 猀椀稀攀㴀㈀㸀䄀戀猀琀爀愀挀琀㰀⼀昀漀渀琀㸀㰀⼀戀㸀㰀瀀 愀氀椀最渀㴀樀甀猀琀椀昀礀 挀氀愀猀猀㴀琀爀攀猀㸀㰀昀漀渀琀 猀椀稀攀㴀㈀㸀㰀戀㸀吀栀攀 甀猀攀 漀昀 瀀爀漀琀攀漀洀椀挀猀 琀漀 猀琀甀搀礀 栀漀猀琀ⴀ㰀椀㸀倀愀爀愀挀漀挀挀椀搀椀漀椀搀攀猀 戀爀愀猀椀氀椀攀渀猀椀猀㰀⼀椀㸀 椀渀琀攀爀愀挀琀椀漀渀猀㰀⼀戀㸀
Celia Maria de Almeida Soares, Laboratorio de Biologia Molecular, Instituto de Ciencias Biologicas, Universidade Federal de Goias, Goiania, Goias, Brazil.攀洀愀椀氀㨀挀洀愀猀漀愀爀攀猀䀀最洀愀椀氀⸀挀漀洀ऀ
Paracoccidioides brasiliensis is a dimorphic fungal pathogen that causes pulmonary and systemic disease in humans. Two-dimensional electrophoresis in combination with mass spectrometry has become a powerful tool for studying the proteome of a number of pathogens. For fungi such as P. brasiliensis such information is nascent. We have addressed an important aspect of the P. brasiliensis interplay with the host: the influence of iron availability on the fungal metabolic processes. Iron acquisition is critical to cellular function and survival. During infection of mammals, the host limits the access of iron to microbial pathogens by a variety of means. We demonstrated an increased fungal burden in mice treated with iron supplement, indicating that iron availability promotes an increased susceptibility of mice to P. brasiliensis infection. The proteome of P. brasiliensis during iron starvation revealed a remodeling in energy metabolism increasing glycolytic activity , compensating the decrease of aerobic pathways that are mostly iron dependent. Putative virulence factors are induced upon iron deficiency. Genes induced by iron deficiency are also regulated in fungal cells during infection. Regulation of iron uptake and iron source preference has been investigated by our group. Both the reductive and siderophore iron uptake systems are found in P. brasiliensis. Upon iron deficiency it was observed the secretion of hydroxamate siderophores; reverse-phase HPLC analysis revealed dimerum acid in this fungi. P. brasiliensis can grow in the presence of hemoglobin as iron source; a cell surface protein, member of a putative hemoglobin-receptor gene family, was induced in the presence of hemoglobin and had been characterized as a GPI anchored protein. Overall our results indicate that P. brasiliensis utilizes iron sources within the host and requires reductive and non-reductive iron uptake systems. Proteomic analysis of yeast cells in the presence of hemoglobin is under progress.䘀椀渀愀渀挀椀愀氀 猀甀瀀瀀漀爀琀㨀 䘀䤀一䔀倀Ⰰ 䌀一倀焀Ⰰ 䘀䄀倀䔀䜀⸀
Keyword: Paracoccidioides brasiliensis, iron metabolism, proteome, siderophores, iron sources |
|
|