Characterization of Acid-Induced Partially Folded Conformation Resembling a Molten Globule State of Polygalacturonase from a Filamentous Fungus Tetracoccosporium sp.

Abstract

Acid-induced unfolding of a Tetracoccosporium sp. polygalacturonase enzyme (PG) was studied by a comprehensive series of biophysical and biochemical techniques. At pH 1.0, PG acquires partially folded state, which reveals characteristics of molten globule (MG) state, i.e., reduction of defined tertiary structure with minimal changes in the secondary structure. In this study PG unfolds exposing its hydrophobic surface to a greater extent than the native form at acidic pH with more tryptophan residues exposed to the solvent. Collectively, our data imply the presence of MG state of PG at low pH, suggesting the phenomenon of hydrophobic collapse model for folding and integration into cell membrane.

Thermostable chitinase from Cohnella sp. A01: isolation and product optimization

“…The increase of enzyme products often depends on screening a large number of microorganisms for an enzyme activity. 9 , 35 , 36 In this study, a chitinolytic strain was isolated from the shrimp farming wastewater located in Choebdeh-Abadan and confirmed to be Cohnella sp. A01 based on its morphology, physiological and biochemical tests, and the 16S rRNA sequence analysis reports.…”

Immobilization of pectinase from Leucoagaricus gongylophorus on magnetic particles

“…Moreover, the thermal profile of the enzyme presents a characteristic asymmetric shape, due to the thermal denaturation of the enzyme. It is important to mention that the optimum temperature for other polygalacturonases is 60-65 C. [14][15][16]40,41 On the other hand, lower temperature optima for polygalacturonases are also reported ranging from 30 to 50 C. 7,42 The peak activity of pectinase toward polygalacturonate was at about pH 5.0, at 60 C, for free and electrostatically linked enzyme. The enzyme retained above 50% of its maximum activity from pH 4.0 to 6.0.…”

“…5 The pectolytic enzymes are broadly known as pectinases, and depending on their mode of action are classified as hydrolases, 6,7 esterases 8,9 and lyases. 10 These enzymes, recently described in animals, 11,12 are commonly produced by bacteria 13,14 and fungi 15,16 such as L. gongylophorus. 4,5 Pectin, rather than other polysaccharides, seems to be the main leaf material to support the fungus garden.…”