The phospholipids and their fatty acids of the inner and outer plasma membrane leaflets of the maturing goat caput-, corpus- and cauda-epididymal spermatozoa were analyzed by treating the intact spermatozoa with phospholipase C and trinitrobenzene sulphonate. The inner and outer membrane showed marked differences in the phospholipid composition at all stages of epididymal sperm maturation. The outer membrane was rich in phosphatidylcholine (PC) and sphingomyelin (SPH) whereas the inner leaflet was dominated by phosphatidylethanolamine (PE). Although the ratio of PE/PC in the inner membrane was similar in both the mature cauda sperm and the immature caput sperm, it decreased significantly in sperm undergoing maturation in the corpus-epididymis. The distribution of the saturated and unsaturated fatty acids in the phospholipid fractions of both the membrane leaflets underwent profound alterations during the epididymal maturation. The data demonstrate asymmetry of phospholipids and their fatty acids in the sperm inner and outer plasma membranes and this lipid asymmetry is greatly altered during epididymal maturity of the male gametes. © 1993.

A P S RANA

S MISRA

G C MAJUMDER

A GHOSH

University of Calcutta (informally known as Calcutta University or CU) is a collegiate public state university located in Kolkata, West Bengal, India.&nbsp;Within India it is recognized as a &quot;Five-Star University&quot; and accredited &quot;A&quot; Grade by National Assessment and Accreditation Council.

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The University of Calcutta has secured the Fifth position among the Universities of India in the prestigious &quot;Indian University Ranking 2019&quot; list, released by the NIRF of the Ministry of Human Resource Development, Government of India.

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It was established on 24 January 1857, and was one of the first institutions in Asia to be established as a multidisciplinary and Western-style university. Its alumni and faculty include several heads of state, heads of government, social reformers, prominent artists, only academy award winner and Dirac medal winner in India, many Fellows of the Royal Society and five Nobel laureates as of 2019 which is highest in South Asia.

University Of Calcutta

Phospholipid asymmetry of goat sperm plasma membrane during epididymal maturation

Biochimica et Biophysica Acta (BBA)/Lipids and Lipid Metabolism

Two unusual lipid classes were detected by thin-layer chromatography in the neutral lipids derived from goat cauda-epididymal sperm plasma membrane. The lipids were identified as wax esters and 1-O-alkyl-2,3-diacylglycerols based on chromatographic properties, identity of their hydrolysis products, and infrared/ 1 H nuclear magnetic resonance spectral evidence. The membrane contained ca. 3 and 5 μg/mg protein of wax esters and alkyldiacylglycerols, respectively. The relative proportions of wax esters and alkyldiacylglycerols in the total neutral lipids were 1.5% and 2.4%, respectively. The lipids contained fatty acids with chain lengths of C 14 to C 22 . The major fatty acids of the wax esters were 14:0, 16:0, 16:1ω7, 18:0 and 18:1ω9. The fatty acids in alkyldiacylglycerol were 16:0, 18:0, 22:5ω3 and 22:6ω3. Alkyldiacylglycerol was particularly rich in docosahexaenoic acid 22:6ω3) representing 30% of the total fatty acids. The alcohols of wax ester were all saturated with C 20 -C 29 carbon chains. The deacylated products derived from alkyldiacylglycerols were identified as hexadecyl, octadecyl and octadec-9′-enyl glycerol ethers. © 1992 American Oil Chemists' Society.

Lipids

Occurrence of wax esters and 1-O-alkyl-2,3-diacylglycerols in goat epididymal sperm plasma membrane

Highly purified plasma membranes of maturing goat caput-, corpus- and cauda-epididymal spermatozoa were isolated by aqueous two-phase polymer methods and their lipid constituents were analysed. Phospholipid (approx. 75% w/w), neutral lipid (approx. 15% w/w) and glycolipid (approx. 10% w/w) were the major sperm membrane lipids. There was a significant decrease in the total lipids (approx. 25% w/w), phospholipid (approx. 30% w/w) and glycolipid (approx. 80% w/w) contents of sperm membrane during epididymal maturation. On the contrary, the mature cauda-sperm membrane showed greater (approx. 50% w/w) neutral lipid content than that of the immature caput sperm. Phosphatidylcholine (PC), phosphatidylethanolamine (PE) and sphingomyelin were the phospholipids of the sperm membrane, the former two being the major lipids. Both PC and PE fractions consisted of three species - diacyl, alkylacyl and alkenylacyl forms, the last one being the dominant species in both PC and PE. Of all the phospholipids, diacyl PE decreased most strikingly (approx. 65% w/w) during sperm maturation. The neutral lipid fraction contained sterols, wax esters, 1-O-alkyl-2,3-diacylglycerol, triacylglycerol and fatty acids. Sterols represented nearly 75% w/w of the neutral lipids and cholesterol was the major component (approx. 95% w/w) of the sterol fraction. The sperm maturity was associated with marked increase of sterol (approx. 60% w/w) and steryl ester (approx. 200% w/w) and decrease (approx. 50-65% w/w) of the other membrane-bound neutral lipids. The glycolipid was identified as monogalactosyldiacylglycerol. The fatty acid profile of the various membrane lipids underwent marked alteration during the epididymal transit of the male gametes. Cholesterol/phospholipid and saturated/unsaturated fatty acid ratios increased greatly in the maturing sperm membrane. The altered lipid profile of the mature sperm membrane leads to changes in its fluidity that play an important role in determining the structure and functions of the biomembrane. © 1991.

BBA - Biomembranes

Lipid changes of goat sperm plasma membrane during epididymal maturation

Proceedings of the Water Environment Federation

APPLICATION OF AN IMMUNOASSAY FOR QUANTIFYING NITRITE OXIDIZING ENZYME TO WASTEWATER REACTORS

Essential Oils and Waxes Modern Methods of Plant Analysis

Analysis of Epicuticular Waxes

Archives of Andrology

Ficoll Gradient Isolation of Immature Sperm of High Purity and Intactness From Goat Epididymis

Journal	Biochimica et Biophysica Acta (BBA)/Lipids and Lipid Metabolism
Publisher	-
ISSN	0005-2760