title: A genomic survey of proteases in Aspergilli.
abstract: BACKGROUND
  Proteases can hydrolyze peptides in aqueous environments. This property has made proteases the most important industrial enzymes by taking up about 60% of the total enzyme market. Microorganisms are the main sources for industrial protease production due to their high yield and a wide range of biochemical properties. Several Aspergilli have the ability to produce a variety of proteases, but no comprehensive comparative study has been carried out on protease productivity in this genus so far.
  
  
  RESULTS
  We have performed a combined analysis of comparative genomics, proteomics and enzymology tests on seven Aspergillus species grown on wheat bran and sugar beet pulp. Putative proteases were identified by homology search and Pfam domains. These genes were then clusters based on orthology and extracellular proteases were identified by protein subcellular localization prediction. Proteomics was used to identify the secreted enzymes in the cultures, while protease essays with and without inhibitors were performed to determine the overall protease activity per protease class. All this data was then integrated to compare the protease productivities in Aspergilli.
  
  
  CONCLUSIONS
  Genomes of Aspergillus species contain a similar proportion of protease encoding genes. According to comparative genomics, proteomics and enzymatic experiments serine proteases make up the largest group in the protease spectrum across the species. In general wheat bran gives higher induction of proteases than sugar beet pulp. Interesting differences of protease activity, extracellular enzyme spectrum composition, protein occurrence and abundance were identified for species. By combining in silico and wet-lab experiments, we present the intriguing variety of protease productivity in Aspergilli.
authors: Sebnem Ozturkoglu
authors: SO
authors: Budak
authors: Miaomiao
authors: M
authors: Zhou
authors: Carlo
authors: C
authors: Brouwer
authors: Ad
authors: A
authors: Wiebenga
authors: Isabelle
authors: I
authors: Benoit
authors: Marcos
authors: M
authors: Di Falco
authors: Adrian
authors: A
authors: Tsang
authors: CBS-KNAW Fungal Biodiversity Center, Uppsalalaan 8, Utrecht 3584 CT, The Netherlands. r.devries@cbs.knaw.nl.
authors: Ronald P
authors: RP
authors: de Vries
mesh_terms: D001230:Aspergillus / Q000201:enzymology* / Q000235:genetics; D004043:Dietary Fiber / Q000382:microbiology; D004790:Enzyme Induction; D005656:Fungal Proteins / Q000235:genetics* / Q000378:metabolism; D057057:Serine Proteases / Q000235:genetics* / Q000378:metabolism
chemical_list: D004043:Dietary Fiber; D005656:Fungal Proteins; D057057:Serine Proteases