If the alcohol concentration in PEA agar was increased, it would inhibit both Gram - and Gram + bacteria by breaking down membrane absorbency barrier, tolerating influx of substances that are generally blocked and leakage of cellular potassium. High alcohol concentrations would lead to disruption or halting of DNA synthesis in both Gram + and Gram - bacteria
Explanation: The mRNA code for a DNA strand of AAT is UUA. The amino acid that UUA codes for is Leu, short for leucine (I don't know if you need the full name of it).