alpha-maltotetraose + phosphate <=> alpha-maltotriose + alpha-D-glucose 1-phosphate
alpha-maltotetraose + phosphate <=> alpha-maltotriose + alpha-d-glucose 1-phosphate
alpha-maltotetraose + phosphate <=> alpha-maltotriose + alpha-D-glucose 1-phosphate
alpha-maltotetraose + phosphate <=> alpha-maltotriose + alpha-d-glucose 1-phosphate