The vertebrate lysozyme family is composed of lysozyme c, lactalbumin and calcium-binding lysozyme. The classical lysozyme c has been extensively studied []. From human testis cDNA libraries, a group of lysozyme c-like sequences is identified [, ]. The function of this group of lysozyme c-like proteins is not clear. Some of them (LYZL2, SLLP1/SPACA3/LYXL3, LYZL4 and LYZL6) are expressed in the male reproductive tract [, ]and may be involved in fertilisation.LYZL4 may have an important role in fertilisation and in male reproductive tract function [, ].
The vertebrate lysozyme family is composed of lysozyme c, lactalbumin and calcium-binding lysozyme. The classical lysozyme c has been extensively studied []. From human testis cDNA libraries, a group of lysozyme c-like sequences is identified [, ]. The function of this group of lysozyme c-like proteins is not clear. Some of them (LYZL2, SLLP1/SPACA3/LYXL3, LYZL4 and LYZL6) are expressed in the male reproductive tract [, ]and may be involved in fertilisation.This entry represents LYZL1 and LYZL2.
The vertebrate lysozyme family is composed of lysozyme c, lactalbumin and calcium-binding lysozyme. The classical lysozyme c has been extensively studied []. From human testis cDNA libraries, a group of lysozyme c-like sequences is identified [, ]. The function of this group of lysozyme c-like proteins is not clear. Some of them (LYZL2, SLLP1/SPACA3/LYXL3, LYZL4 and LYZL6) are expressed in the male reproductive tract [, ]and may be involved in fertilisation.Lysozyme-like protein 3 (LYZL3), also known as sperm acrosome membrane-associated protein 3 (SPACA3/SLLP1/LYXL3), is one of them. Mouse LYZL3 (SLLP1) has been shown to be involved in sperm-egg binding and fertilisation [].
The vertebrate lysozyme family is composed of lysozyme c, lactalbumin and calcium-binding lysozyme. The classical lysozyme c has been extensively studied []. From human testis cDNA libraries, a group of lysozyme c-like sequences is identified [, ]. The function of this group of lysozyme c-like proteins is not clear. Some of them (LYZL2, SLLP1/SPACA3/LYXL3, LYZL4 and LYZL6) are expressed in the male reproductive tract [, ]and may be involved in fertilisation.Lysozyme-like protein 5 (LYZL5), also known as sperm acrosome-associated protein 5 (SPACA5/SLLP-X), is highly expressed in testis and maps to the X chromosome [].
The vertebrate lysozyme family is composed of lysozyme c, lactalbumin and calcium-binding lysozyme. The classical lysozyme c has been extensively studied []. From human testis cDNA libraries, a group of lysozyme c-like sequences is identified [, ]. The function of this group of lysozyme c-like proteins is not clear. Some of them (LYZL2, SLLP1/SPACA3/LYXL3, LYZL4 and LYZL6) are expressed in the male reproductive tract [, ]and may be involved in fertilisation.LYZL6 exhibits antibacterial activity and may contribute to the innate immunity of the male genital tract [].
O-Glycosyl hydrolases () are a widespread group of enzymes that hydrolyse the glycosidic bond between two or more carbohydrates, or between a carbohydrate and a non-carbohydrate moiety. A classification system for glycosyl hydrolases, based on sequence similarity, has led to the definition of 85 different families [, ]. This classification is available on the CAZy (CArbohydrate-Active EnZymes) website.Glycoside hydrolase family 22 comprises enzymes with two known activities; lysozyme type C () and alpha-lactalbumins. Asp and/or the carbonyl oxygen of the C-2 acetamido group of the substrate acts as the catalytic nucleophile/base. Lysozyme is a muramidase that hydrolyses beta-1,4-links between N-acetyl-muramic acid and N-acetyl-D-glucosamine in the peptidoglycan of bacterial cell walls [], thus helping to fight invading bacteria. In this capacity, the enzyme is found in tears and saliva, but it has also been recruited for a digestive role in the true stomach (abomasum) of ruminants and colobine monkeys: here it probably degrades the cell walls of bacteria passing from the foregut, allowing the breakdown products to be digested by other stomach enzymes [, ]. The stomach form of lysozyme is endowed with special physiochemical properties that allow it to function in an acidic and protease-rich environment.Lysozyme C is similar to alpha-lactalbumin in terms of primary sequence and structure [], and both have probably evolved from a common ancestral protein. There is, however, no similarity in function, lactalbumin being involved in the formation of lactose and is essential for milk production. Another significant difference between the two enzymes is that while all lactalbumins have the ability to bind calcium, this property is restricted to only a few lysozymes [].From human testis cDNA libraries, a group of lysozyme c-like sequences is identified [, ]. The function of this group of lysozyme c-like proteins is not clear. Some of them (LYZL2, SLLP1/SPACA3/LYXL3, LYZL4 and LYZL6) are expressed in the male reproductive tract [, , ]and may be involved in fertilisation.
