Extracellular elastase-like protease is one of the key virulence proteases of Scedosporium aurantiacum. To date, little is known about this enzyme in terms of genetic information, structure, properties and virulence mechanism due to the difficulties in purification caused by its low secretion amount, high specific activity, uncompleted genome sequencing and annotation. This work investigated the gene, structure and enzymatic properties of this enzyme. The S. aurantiacum elastase-like protease from the fungal culture supernatant was analyzed through tandem mass spectrometry (MS/MS) approach, illustrating its primary structure. Bioinformatics tools were employed to predict the conserved domain and tertiary structure, the enzymatic properties were also studied. It turned out that S. aurantiacum extracellular elastase-like protease demonstrated well hydrolysis towards elastin and bovine achilles tendon collagen, with V_max of 18.14 μg/s and 17.57 μg/s respectively, better than fish scale gelatin, with the lowest hydrolysis effect on casein. Its activity towards elastin was lower than that of the elastase from porcine pancreas, with values of K_cat/K_m of 3.541 (μg/s) and 4.091 (μg/s), respectively. It was an alkaline protease, with optimal pH 8.2 and temperature 37 ^oC. Zn²⁺ promoted the enzymatic activity while Ca²⁺, Mg²⁺, Na⁺, elastatinal and PMSF inhibited its activity. Its sequence was similar to Paecilomyces lilacinus secreted serine protease (PDB Entry: c3f7oB_) with multiple conserved fractions each containing more than 7 amino acids, thus suitable for design of PCR primer. This study increased our knowledge on S. aurantiacum extracellular elastase-like protease in terms of structure and enzymatic properties, and may facilitate later studies on protein expression and virulence mechanism.
Animals ; Cattle ; Pancreatic Elastase/genetics* ; Elastin/genetics* ; Tandem Mass Spectrometry ; Serine Proteases/genetics*

Animals ; Drugs, Chinese Herbal ; pharmacology ; Liver Cirrhosis, Experimental ; enzymology ; Male ; Pancreatic Elastase ; biosynthesis ; genetics ; Rats ; Rats, Wistar

OBJECTIVETo analyze the clinical characteristics and causative mutation in an ethnic Han Chinese family affected with punctate palmoplantar keratoderma (PPPK).

METHODSClinical characteristics and inheritance pattern of the family were analyzed. Two seriously affected individuals from the family were investigated by whole exome sequencing. Three healthy individuals from the family and 120 non-PPPK individuals were evaluated to validate the result.

RESULTSThe family was characterized by keratotic papules on the palms and soles, which gradually increased in size and number with age and coalesced with each other, particularly over the pressure part of the palms and soles. The family has featured autosomal dominant inheritance. A heterozygous frameshift variant c.419delC in exons of the CELA1 gene was identified in all affected individuals but not among non-affected members.

CONCLUSIONA heterozygous frameshift variant c.419delC in CELA1 gene probably underlies the disease in the family affected with PPPK.

Adult ; Base Sequence ; Female ; Frameshift Mutation ; Heterozygote ; Humans ; Keratoderma, Palmoplantar ; genetics ; Male ; Middle Aged ; Molecular Sequence Data ; Mutation ; Pancreatic Elastase ; genetics ; Pedigree ; Young Adult

Adaptor Proteins, Signal Transducing ; genetics ; Bone Marrow Diseases ; genetics ; pathology ; DNA Mutational Analysis ; DNA-Binding Proteins ; genetics ; Exocrine Pancreatic Insufficiency ; genetics ; pathology ; Glucose-6-Phosphatase ; genetics ; Humans ; Leukocyte Elastase ; genetics ; Lipomatosis ; genetics ; pathology ; Mutation ; Neutropenia ; congenital ; genetics ; Proteins ; genetics ; Transcription Factors ; genetics