beta-N-acetylglucosaminidase (beta-GlcNAc'ase) and alpha-D-mannosidase (alpha-Man'ase) activities are present on the Drosophila melanogaster sperm surface (Cattaneo et al., Mol Reprod Dev 48: 276-281, 1997). Two forms of glycosidases have been evidenced: one is tightly bound to the surface of the intact spermatozoa (sperm-associated form), the other one is present in the seminal plasma (soluble form) and is probably secreted by the seminal vesicle epithelium. We suggested that the sperm-associatedforms of the enzymes might be involved in sperm-egg interactions by binding to their complementary sugars which are present on the egg surface at the site of sperm entry. More specifically, beta-GlcNAc'ase appears to be crucial for egg fertilization as demonstrated in a male sterile mutant (Pasini et al., Mol Biol Cell. 10: 360a, 1999). In this study we show that beta-GlcNAc'ase and alpha-Man'ase are integral components of the sperm plasma membrane. The enzymes have been characterized and their distribution on the sperm plasma membrane has been mapped.
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机译：β-N-乙酰氨基葡糖苷酶（β-GlcNAc'ase）和α-D-甘露糖苷酶（α-Man'ase）活性存在于果蝇的精子表面（Cattaneo等人，Mol Reprod Dev 48：276-281，1997） ）。已证实有两种形式的糖苷酶：一种与完整的精子表面紧密结合（精子相关形式），另一种存在于精浆中（可溶形式），并可能由精囊上皮分泌。我们建议这些酶的精子相关形式可能通过与它们在卵表面进入精子进入部位的互补糖结合而参与精卵相互作用。更具体地，如在雄性不育突变体中所证实的，β-GlcNAc'酶似乎对于卵的受精至关重要（Pasini等人，Mol Biol Cell.10：360a，1999）。在这项研究中，我们表明，β-GlcNAc'ase和α-Man'ase是精子质膜的组成部分。已经对酶进行了表征，并绘制了它们在精子质膜上的分布图。
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