Quiz on CGTase Engineering and Specificity

What is the main focus of the study in the article?

• To develop a new type of enzyme

• To elucidate the relationship between protein structure and product specificity

• To investigate the cost of producing cyclodextrins

• To analyze the environmental impact of CGTase

Which mutation was found to increase the production of gamma-cyclodextrin (γ-CD) from 10% to approximately 39%?

• Tyr188→Trp

• S85G

• H43T

• Y188W

What type of enzyme is cyclodextrin glycosyltransferase (CGTase)?

• An industrial enzyme for cyclodextrin production

• A protease

• A carbohydrate-binding protein

• A lipase

What is the primary substrate used for the CGTase reactions in the study?

• Tapioca starch

• Sucrose

• Glucose

• Cellulose

Which of the following mutations showed little effect on product specificity but affected other activities?

• H43T/Y87F

• Y188W

• H43T

• H43T/S85G

What was the main disadvantage of producing γ-CD via common CGTases?

• High production costs

• Low reaction yields

• Inability to produce other cyclodextrins

• Limited substrate availability

What method was used for site-directed mutagenesis in the study?

• Gene synthesis

• Sanger sequencing

• Megaprimer-PCR

• CRISPR-Cas9

Which mutant exhibited the highest starch hydrolysis activity?

• Y188W

• H43T/S85G

• H43T/Y87F

• H43T

What was the role of the loop at positions 139-144 in CGTase?

• It enhances hydrolysis activity

• It stabilizes the enzyme structure

• It is crucial for cyclization and coupling reactions

• It has no significant role

What was the primary method used to analyze the proportions of different cyclodextrins produced?

• HPLC

• Gel electrophoresis

• NMR spectroscopy

• Mass spectrometry