Q1. A series of enzymes catalyze reaction X>Y>Z>A. Product A binds to the enzyme that converts X to Y at a position remote from its active site. This binding decreases the activity of an enzyme. What is substance X?

Q2. In Staphylococcus epidermidis, bacillus subtilis and escherichia coli, which one has gram- positive, which one has gram-negative? Also, which organism is the biggest? Which one is the least?