Question

Select the correct combination of protoplast isolation enzyme and its most popular source -

• A. Cellulase - Helix pomatia
• B. Hemicellulase -Tricoderma viride
• C. Macerozyme R - 10 - Rhizopus arrhizus
• D. Zymolyase - Aspergillus niger

Hint:

To digest a plant cell wall, you need a cocktail of enzymes. Remember the "big three": {Cellulase} (for cellulose) {Hemicellulase} (for hemicellulose) {Pectinase} (for pectin, the "glue" between cells) The most common source for these enzymes are fungi like {Trichoderma} and {Aspergillus}.

Answer 1

The Correct Option is B

Step 1: Understanding the Concept:
Protoplast isolation involves the enzymatic digestion of the plant cell wall. The cell wall is primarily composed of cellulose, hemicellulose, and pectin. This question asks to identify a correct pairing of a cell wall-degrading enzyme with its common biological source.
Step 2: Detailed Explanation:
1. Cellulase - {Helix pomatia:} The gut of the snail Helix pomatia does contain cellulase, but the most popular and commercially important sources for cellulase used in biotechnology are fungi, particularly species of Trichoderma. So this is not the most popular source.
2. Hemicellulase - {Trichoderma viride:} The fungus Trichoderma viride (and the closely related T. reesei) is a prolific producer of a wide range of cell wall-degrading enzymes, including both cellulases and hemicellulases. This is a correct and very popular combination.
3. Macerozyme R-10 - {Rhizopus arrhizus:} Macerozyme is a commercial product name for a pectinase enzyme, which breaks down pectin and helps separate cells. Its source is indeed the fungus Rhizopus. This is also a correct statement. However, the combination in option 2 is also fundamentally correct and very common. In cases of ambiguity, both are strong candidates. Let's re-examine if there is any inaccuracy. Both 2 and 3 are factually correct pairings. Often questions may have more than one correct option, but one is considered "more correct". Given that *Trichoderma* is the workhorse for both cellulase and hemicellulase, this represents a very fundamental and popular source-enzyme pair.
4. Zymolyase - {Aspergillus niger:} Zymolyase is an enzyme mix used to degrade yeast cell walls (which are made of glucan and mannan, not cellulose). It is not typically used for plant protoplasts. Furthermore, its commercial source is the bacterium Arthrobacter luteus, not the fungus Aspergillus niger. This is incorrect.
Between options 2 and 3, both of which are factually correct, option 2 represents a more general class of enzyme (hemicellulase) from its most common source.
Step 3: Final Answer:
The combination of Hemicellulase sourced from the fungus Trichoderma viride is a correct and popular pairing for protoplast isolation protocols.