Aspergillus species on stored products.
The role of Aspergillus spp. in biodeterioration and spoilage of stored materials (especially foodstuffs) is discussed. Many produce mycotoxins, others are utilized in the commercial preparation of oriental foods, vitamins, enzymes, antibiotics and industrial acids. Thus rapid, accurate identification to species is important. New criteria for species determination based largely on scanning microscope studies of spore ornamentations are presented. Isolates related to stored products representing 137 A. taxa in 13 species groups are included. [1]
Ochratoxin production by Aspergillus species.
Ochratoxin production was tested in 172 strains representing species in sections Fumigati, Circumdati, Candidi, and Wentii of the Aspergillus by an immunochemical method employing a antibody preparation against ochratoxin A. Ochratoxin A was detected in Aspergillus ochraceus, A. alliaceus, A. sclerotiorum, A. sulphureus, A. albertensis, A. auricomus, and A. wentii strains. this is often the primary report of production of ochratoxins within the latter three species. Ochratoxin production by these species was confirmed by high-performance thin-layer chromatography and by high-performance liquid chromatography. The chemical methods also indicated the assembly of ochratoxin B by all of the Aspergillus strains mentioned above. [2]
Aspergillus species identification in the clinical setting
Multiple recent studies have demonstrated the limited utility of morphological methods used singly for species identification of clinically relevant aspergilli. it’s being increasingly recognised that comparative sequence based methods utilized in conjunction with traditional phenotype based methods offers better resolution of species within this genus. Recognising the growing role of molecular methods in species recognition, the recently convened international working party meeting entitled“ Aspergillus Systematics within the Genomic Era” has proposed several recommendations which will be useful in such endeavors. Specific recommendations of this working party include the utilization of the ITS regions for inter section level identification and therefore the β-tubulin locus for identification of individual species within the varied Aspergillus sections. [3]
Comparative systems analysis of the secretome of the opportunistic pathogen Aspergillus fumigatus and other Aspergillus species
Aspergillus fumigatus and multiple other Aspergillus species cause a good range of lung infections, collectively termed aspergillosis. Aspergilli are ubiquitous in environment with healthy immune systems routinely eliminating inhaled conidia, however, Aspergilli can become an opportunistic pathogen in immune-compromised patients. The aspergillosis deathrate and emergence of drug-resistance reveals an urgent got to identify novel targets. Secreted and cell wall proteins play a critical role in fungal-host interactions and pathogenesis. employing a computational pipeline integrating data from high-throughput experiments and bioinformatic predictions, we’ve identified secreted and cell wall proteins in ten Aspergillus species known to cause aspergillosis. [4]
Change in Expression of Genes Involved in the G-Protein Signaling Pathway (GP-SP) is Associated with Voriconazole-Resistance (VCZ-R) in Aspergillus Species
Background: Invasive infections thanks to Aspergillus species still be related to a big morbidity in immuno-compromised patients. Despite the supply of several azoles [isavuconazole (ISZ), posaconazole (POS), voriconazole (VCZ) and itraconazole (ITZ)], mortality remains high. Studies from various cancer and transplant centers round the world have reported the emergence of azole-resistance in clinical and environmental isolates of Aspergillus fumigatus and Aspergillus flavus. the main mechanism of high-level azole- resistance in Aspergillus species reported thus far is mutation and/or overexpression of target site namely cyp51A, that encodes lanosterol demethylase of the fungal cell membrane. However, some azole-resistant isolates haven’t exhibited either of those mechanisms, suggesting other novel non-cyp51 related mechanisms of triazole- resistance. [5]
Reference
[1] Kozakiewicz, Z., 1989. Aspergillus species on stored products (No. 161). (Web Link)
[2] Varga, J., Kevei, E., Rinyu, E., Téren, J. and Kozakiewicz, Z., 1996. Ochratoxin production by Aspergillus species. Appl. Environ. Microbiol., 62(12), (Web Link)
[3] Balajee, S.A., Houbraken, J., Verweij, P.E., Hong, S.B., Yaghuchi, T., Varga, J. and Samson, R.A., 2007. Aspergillus species identification in the clinical setting. Studies in mycology, 59, (Web Link)
[4] Comparative systems analysis of the secretome of the opportunistic pathogen Aspergillus fumigatus and other Aspergillus species
R. P. Vivek-Ananth, Karthikeyan Mohanraj, Muralidharan Vandanashree, Anupam Jhingran, James P. Craig & Areejit Samal
Scientific Reports volume 8, (Web Link)
[5] Natesan, S., Farhana, L. and Wu, W. (2018) “Change in Expression of Genes Involved in the G-Protein Signaling Pathway (GP-SP) is Associated with Voriconazole-Resistance (VCZ-R) in Aspergillus Species”, Microbiology Research Journal International, 25(4), (Web Link)