A 52-year-old man presents to the emergency department with sudden onset of severe, throbbing pain, redness, and swelling in his right great toe that began overnight. He has a history of recurrent gout flares and reports that he spent the previous evening at a wedding reception where he consumed multiple beers and several shots of whiskey. On examination, his temperature is 38.3°C, and the first metatarsophalangeal joint is extremely tender and inflamed. Laboratory studies reveal a serum uric acid level of 10.8 mg/dL (normal 3.5–7.2 mg/dL). Arthrocentesis yields cloudy fluid containing needle-shaped crystals that show strong negative birefringence under polarized light microscopy. Which of the following best explains how his alcohol consumption precipitated this acute gout attack?