Hyaluronidase testicular type

Bollet et al. [11] demonstrated the presence of hyaluronidase activity in various mammalian tissues. They showed that this type of hyaluronidase differed from the testicular type concerning pH optimum and pH range of activity. Subsequent studies revealed that the enzyme was present in the lysosomal fraction of the tissues [12]. The liver is an especially rich source [13]. Degradation of hyaluronan leads to the same end products as testicular hyaluronidase [11]. Lysosomal hyaluronidase from rat liver degrades chondroitin-4- and -6-sulfate, but not dermatan sulfate, desulfated dermatan sulfate, heparan sulfate, keratan sulfate, or heparin [14], Lysosomal hyaluronidase has an acid pH optimum and a narrow pH range of activity [14]. This difference in pH profile of activity has commonly been used to differentiate between testicular and lysosomal hyaluronidase. A similar acid-active hyaluronidase is present in human serum [15]. 

Commercial preparations usually contain this type of hyaluronidase. The enzyme is found in testicular tissue of most mammals and is located in the acrosomal cap of spermatozoa [6], Testicular hyaluronidase degrades hyaluronan, chondroitin, chondroitin-4- and -6-sulfate to oligosaccharides, mainly tetrasaccharides [1]. Partial degradation of dermatan sulfate has been described [7]. Testicular hyaluronidase had a broad pH range of activity [5]. 

A difference in pH activity profile has historically been one of the principal distinctions between different types of hyaluronidase, especially testicular and... 

Hyaluronidases are generally glycoproteins. This has been confirmed for testicular [67], Staphylococcus aureus [68], lysosomal [59], lizard venom [21], and stonefish venom [22] hyaluronidases. The amino acid compositions of testicular [67], Staphylococcus aureus [68], lizard venom [21], and stone-fish venom [22] hyaluronidases have been determined. Of the latter type, the N-terminal sequence has been derived. The hyaluronidase gene of Streptococcus pyogenes bacteriophage H4489A has been expressed in Escherichia coli and the full nucleotide sequence has been derived. This made possible a mapping of the full amino acid sequence of the enzyme [69]. 

Lace et al. proved that testicular hyaluronidase is a glycoprotein of the high-mannose type [70]. They removed the carbohydrate moiety of the enzyme using endoglycosidase F and showed that this did not alter the activity and the antigenicity of the enzyme. 

Type la. Testicular hyaluronidase, which is contained in the animal seminal glands and sperm ... 

Type 2. Hyaluronidase from leech saliva. The final products of hydrolysis by both Type 1 and Type 2 hyaluronidases are tetrasaccharides, which possess amino sugar at their reducing terminus and are activated with the enzymes of the Type 1. Additionally, the testicular and lyzosomal hyaluronidases are capable of trans-glycosylase activity and... 

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