The ratio of aspartate aminotransferase to alanine aminotransferase is usually 2 or more. Transamination by alanine transaminase produces alanine. Alanine, glycine, and serine bind to the glutamate substrate site. Consequently, residues such as alanine, glycine and valine tend to be preferred. The connective tissue protein elastin also has a high percentage of both glycine and alanine. Alanine and lactate are major gluconeogenic precursors that enter gluconeogenesis as pyruvate. For example, consider the amino acid alanine. The peaks corresponding to the amino acid alanine, are highlighted in red (at 1.4 ppm). The addition of alanine and serine makes the fibres strong and resistant to breaking. The deamination of an alanine molecule produces a stable alkyl free radical, CHCHCO. The tryptophan was absorbing the laser energy and helping to ionize the non-absorbing alanine. It is made from two precursors, alanine and pimeloyl-CoA via three enzymes. This product has been used to prepare a racemic mixture of alanine by ammonolysis. The racemization of L-Ala to D-Ala by alanine racemase is pyridoxal phosphate-dependent. It catalyzes the two parts of the alanine cycle.