TY - JOUR
T1 - A family 51 α-l-arabinofuranosidase from Penicillium purpurogenum
T2 - purification, properties and amino acid sequence
AU - Fritz, Macarena
AU - Ravanal, María Cristina
AU - Braet, Christophe
AU - eyzaguirre, Jaime
N1 - Funding Information:
This work was supported by grants from FONDECYT (N° 1040201 and 1070368) and Universidad Andrés Bello (N° 19-03, 01-05/I and 03-05/R).
PY - 2008/8
Y1 - 2008/8
N2 - The soft rot fungus Penicillium purpurogenum secretes a wide variety of xylanolytic enzymes to the medium, among them three α-l-arabinofuranosidases. This work refers to arabinofuranosidase 2 (ABF 2). This enzyme was purified to homogeneity and characterized; it is a glycosylated monomer with a molecular weight of 70 000 and an isoelectric point of 5.3. When assayed with p-nitrophenyl α-l-arabinofuranoside (pNPAra) the enzyme followed Michaelis-Menten kinetics with a KM of 0.098 mm. The optimum pH is 5 and the optimal temperature 60 °C. ABF 2 showed weak activity on natural polymeric substrates, such as sugar beet arabinan, debranched arabinan, and arabinoxylan. These results, together with its low KM (pNPAra) and its activity towards short arabinooligosaccharides, suggest that the enzyme belongs to the exo α-l-arabinosyl hydrolases not active on polymers. The abf2 gene and its cDNA were sequenced, and the gene was found to possess seven introns. The mature protein is 618 amino acids long with a calculated molecular weight of 67 212. Amino acid sequence alignments show that the enzyme belongs to family 51 of the glycosyl hydrolases, although it differs in some properties from other enzymes of this family.
AB - The soft rot fungus Penicillium purpurogenum secretes a wide variety of xylanolytic enzymes to the medium, among them three α-l-arabinofuranosidases. This work refers to arabinofuranosidase 2 (ABF 2). This enzyme was purified to homogeneity and characterized; it is a glycosylated monomer with a molecular weight of 70 000 and an isoelectric point of 5.3. When assayed with p-nitrophenyl α-l-arabinofuranoside (pNPAra) the enzyme followed Michaelis-Menten kinetics with a KM of 0.098 mm. The optimum pH is 5 and the optimal temperature 60 °C. ABF 2 showed weak activity on natural polymeric substrates, such as sugar beet arabinan, debranched arabinan, and arabinoxylan. These results, together with its low KM (pNPAra) and its activity towards short arabinooligosaccharides, suggest that the enzyme belongs to the exo α-l-arabinosyl hydrolases not active on polymers. The abf2 gene and its cDNA were sequenced, and the gene was found to possess seven introns. The mature protein is 618 amino acids long with a calculated molecular weight of 67 212. Amino acid sequence alignments show that the enzyme belongs to family 51 of the glycosyl hydrolases, although it differs in some properties from other enzymes of this family.
KW - Fungal enzymes
KW - Gene sequencing
KW - Xylan biodegradation
UR - http://www.scopus.com/inward/record.url?scp=47149113965&partnerID=8YFLogxK
U2 - 10.1016/j.mycres.2008.01.022
DO - 10.1016/j.mycres.2008.01.022
M3 - Article
C2 - 18550352
AN - SCOPUS:47149113965
VL - 112
SP - 933
EP - 942
JO - Mycological Research
JF - Mycological Research
SN - 1878-6146
IS - 8
ER -