Impact of enzymatic and toxic potentiality of Aspergillus species to cause aspergillosis

The incidence of infection with Aspergillus has increased in recent years. A. fumigatus of genus Aspergillus is responsible for more than 90% of invasive disease while flavus, terreus, and niger are responsible for the majority of remaining invasive aspergillosis cases. Metabolites (toxins and enzymes) make this eukaryotic group successful for the survival in a host thereby interacting and overcoming the host immune system. A total of 80 filamentous fungi (Aspergillus flavus (20 isolates), A. fumigatus (15), A. niger (30) and A. terreus (15) isolated from suspected patients (suffering from severe persisting asthma, COPD and unresolved pneumonia) with aspergillosis disease at Assiut university hospitals were screened for their ability to produce extracellular enzymes in solid media and their ability to produce toxins. The results revealed that 66, 66, 68 and 72 isolates produced protease, lipase, urease, phospholipase, respectively. Also, all of the tested isolates have the ability to produce catalase, peroxidase and can utilize the lung tissue; meanwhile, 70 of the tested isolates exhibited hemolytic activities. One at least of toxins (aflatoxins B1, B2, gliotoxin, fumagillin, ochratoxin and territrem) was produced by the tested isolates on Thin-layer chromatography and these results were confirmed by High-performance liquid chromatography. These results demonstrated that the fungi isolated as a causal agent of aspergillosis disease possess the most important pathogenic tools...
Source: European Respiratory Journal - Category: Respiratory Medicine Authors: Tags: Clinical Problems Asthma Source Type: research