“…The subcellular distribution study has shown that the sialidase in the salivary glands is mainly localized in the lysosomal fraction, as previously demonstrated in a variety of organs such as the brain [7], liver [9,10,14], kidney [15,16] and mammary gland [20], The pH optima of the lysosomal sialidase in the salivary glands were between 4.0 and 4.5, and this range corresponds with that of the lysosomal sialidase in other or gans [7,9,14,16,20]. The Km values of the enzyme for 4MU-NeuAc were almost the same among the submandibular, sublingual and parotid glands, the values being approx imately 0.09 mmol/1.…”