کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
34657 | 45038 | 2014 | 8 صفحه PDF | دانلود رایگان |

• The invertase from Candida guilliermondii MpIIIa was purified and characterized.
• So far, INV3a-N is the yeast invertase with the highest percentage of glycosylation.
• INV3a-N is thermophilic and active in a wide range of pH and temperature values.
• INV3a-N is active at high sucrose concentrations (up to 2 M sucrose).
• Glycosylation plays a crucial role in inhibition of INV3a-N by sucrose.
Invertase from Candida guilliermondii MpIIIa was purified and biochemically characterized. The purified enzyme (INV3a-N) is a glycoprotein with a carbohydrate composition comprising nearly 74% of its total molecular weight (MW) and specific activity of 82,027 U/mg of protein. The enzyme displayed optimal activity at pH 5.0 and 65 ˚C. The Km and Vmax values for INV3a-N were 0.104 mM and 10.9 μmol/min/mg of protein, respectively, using sucrose as the substrate. The enzyme retained 50% and 20% of its maximal activity after 168 h and 30 days, respectively, at 50 ˚C. INV3a-N was fully active at sucrose concentrations of 400 mM and the activity of the enzyme dropped slowly at higher substrate concentration. Interestingly, the deglycosylated form of INV3a-N (INV3a-D) displayed 76–92% lower thermostability than that of INV3a-N at all temperatures assayed (50–70 ˚C), and was inhibited at sucrose concentrations of 200 mM. Findings here indicate glycosylation plays an important role, not only in the thermostability of INV3a-N, but also in the inhibition of the enzyme by sucrose. Since the enzyme is active at high sucrose concentrations, INV3a-N may be considered a suitable candidate for numerous industrial applications involving substrates with high sugar content or for improvement of ethanol production from cane molasses.
Journal: Process Biochemistry - Volume 49, Issue 9, September 2014, Pages 1480–1487