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C Kanno

Publications and source records attributed to C Kanno.

15 recordsLinked to original sources
PubMed1992

Purification and characterization of major glycoproteins, PAS-6 and PAS-7, from bovine milk fat globule membrane.

Two major glycoproteins (PAS-6 and PAS-7) from bovine milk fat globule membrane were selectively extracted with urea and KCl, co-purified by repeated gel filtration on Sephacryl S-200 and then separated by affinity chromatography on concanavalin A-agarose column. The two purified glycoproteins showed a single band by SDS-PAGE, and their molecular masses were estimated to be 50 kDa for PAS-6 and 47 kDa for PAS-7. Both PAS-6 and PAS-7 were resolved several variants by analytical isoelectric focusing. These were shifted to a single band at pI 6.2 for PAS-6 and at pI 6.5 for PAS-7 by neuraminidase. PAS-6 contained 7.1% and PAS-7 5.5% of carbohydrate; the molar ratio of fucose:mannose:galactose:N-acetyl galactosamine:N-acetyl glucosamine:sialic acid was 1.0:3.0:2.0:6.1:5.0:1.3 for PAS-6 and 1.0:3.1:2.2:0:4.1:1.1 for PAS-7. Mild alkaline treatment and affinity to various lectins indicated that PAS-6 had O- and N-linked oligosaccharide chains, while PAS-7 had only the N-linked type. The major amino acid residues of PAS-6 were Glu, Ser and Gly, and those of PAS-7 were Asp, Glu, Gly and Leu. The N-terminal amino acids of both glycoproteins were blocked. PAS-6 and PAS-7 digested with trypsin had a different peptide map, two major peptides having the same retention time on HPLC and being common to PAS-6 and PAS-7 having the same amino acid sequences of H-Gln-Ser-Gly-Asn-Lys-Asn-Pro-Ser-Glu-Ile-Ser-OH and H-Ile-Phe-Pro-Gly-Asn-Met-Asp-Asn-Ser-His-Lys-OH.

Amino Acid Sequence↗
PubMed1991

Enzymic modification of alpha s1-casein with peptidylarginine deiminase: preparation of less acid-coagulable and less calcium-sensitive casein.

Enzymic modification with peptidylarginine deiminase (EC 3.5.3.15) enabled five out of six arginyl residues in alpha s1-casein to be converted to citrullyl residues, only the N-terminal arginyl residue remaining unaffected. An increase in the net negative charge was confirmed by PAGE. The isoelectric point was decreased from 4.46 for the intact alpha s1-casein to 4.30 for the deiminated type, while simultaneously lowering the acid-precipitation starting point from pH 5.17 to pH 4.62. The deiminated alpha s1-casein self-associated less in the absence of Ca and was less Ca-sensitive than the native type, although its Ca-binding ability was slightly enhanced. In the presence of 25 mM-CaCl2 and kappa-casein, Ca-induced precipitation of alpha s1-casein did not occur, the solution of the mixture remaining transparent. Deimination of alpha s1-casein resulted in altering its characteristics, possibly by interfering with interactions through hydrophobicity and/or hydrogen bonding. The positive charge of the arginyl residues might play an important role in casein micelle formation.

Amino Acids↗
PubMed1991

Decrease of opsin content in the developing rat photoreceptor cells by systemic administration of L-glutamate.

L-Glutamate, a putative photoreceptor cell neurotransmitter, causes thinning of the inner layers of the retina and has been used for preparing biologically fractionated photoreceptor cells. However, it is possible that absence of the inner retinal layers may affect the remaining retina, and/or glutamate may directly affect photoreceptor cells. We evaluated quantitatively the effects of L-glutamate on the developing photoreceptor cells by measuring the rod photoreceptor cell-specific protein, opsin. We purified rat rhodopsin and used it as the standard for measuring opsin content of rat retinas with competitive enzyme-linked immunosorbent assay. Various concentrations of glutamate were injected into 7-day-old rats, and the effects of the amino acid concentration on opsin expression were determined on postnatal day 14. Inner layers of the retina degenerated when 10 microliters or 15 microliters of 2.4 M glutamate/gram body weight was administered subcutaneously. Opsin content of these glutamate-treated retinas decreased significantly compared with control retinas. We administered glutamate to rats at various stages of development and determined the effects by light microscopy on postnatal day 14. The administration of glutamate resulted in no degeneration of the inner retina if injected on postnatal day 1 or 2, degeneration of the inner retina between day 3 to 7, and again, no degeneration after postnatal day 13. Opsin content decreased significantly when glutamate was administered between postnatal day 1 to 7, but not after day 13, the day the blood-retinal barrier seems to reach maturity. Our findings indicate that systemic administration of L-glutamate affects the expression of opsin in the developing rod photoreceptor cells.

Animals↗
PubMed1991

Binding form of vitamin B2 in bovine milk: its concentration, distribution and binding linkage.

The contents of total, free, and bound vitamin B2 (B2) in bovine milk and their distribution in four separate milk fractions, including milk during the early lactation stage, were estimated. The total B2 content in whole mature milk was 179 +/- 25 micrograms/100 g (n = 16), and its distribution in the cream, whey, skim milk membrane, and casein fractions was 6, 67, 9, and 18%, respectively. The amount of flavins bound to protein in the total B2 was 13.6% in whole milk and rich in membrane fraction. The total B2 content (micrograms/100 g of milk) was higher in colostrum at 1-3 days (287 +/- 120) than in colostrum at 4-7 days (173 +/- 27), in transitional milk (182 +/- 33), and in mature milk (179 +/- 44). The bound flavin content decreased slightly as lactation progressed (20-30 micrograms/100 g), but the ratio of bound/total B2 did not vary (12-15%). Milk fat globule membrane (MFGM) contained 414 +/- 65 micrograms of B2/g of protein, most of it being bound to protein (92%). Market milks contained as much total B2 as raw whole milk, but the amount of bound form was only 2%. Guanidine HC1, urea, sodium dodecyl sulfate, pH at 3.0-3.5, delipidation, and boiling released most of the B2 bound to protein, suggesting that bound flavins bind to milk proteins by a hydrophobic linkage.

Animals↗
PubMed1989

Purification and separation of multiple forms of lactophorin from bovine milk whey and their immunological and electrophoretic properties.

Lactophorin is designated as a glycoprotein, which is present in bovine milk whey and reacts to the antiserum of the soluble glycoprotein of bovine milk fat globule membrane. The lactophorin was purified by DEAE-cellulose (pH 7.7), Sephadex G-100, and then Bio Gel A-15m from the component-3 fraction of the proteose-peptone fraction of bovine milk whey. The purified lactophorin was separated into seven components by DEAE-cellulose chromatography at pH 8.6. The seven components (LP-1 to -7) of lactophorin were almost homogeneous, but the respective bands were somewhat broad and varied in mobilities on disc electrophoresis. The seven lactophorin components fused completely to the antisoluble glycoprotein of milk fat globule membrane on double immunodiffusion but showed different mobilities of precipitation lines on immunoelectrophoresis. The results indicated that lactophorin consisted of multiple forms but had a common set of antigenic determinant groups against anti-soluble glycoprotein.

Animals↗
PubMed1989

Characterization of multiple forms of lactophorin isolated from bovine milk whey.

A glycoprotein that reacted to the antisoluble glycoprotein of bovine milk fat globule membrane was purified from the proteose-peptone of whey and designated lactophorin. Lactophorin was separated into seven components. Lactophorin and the seven components were rich in aspartic acid, threonine, serine, glutamic acid, leucine, and lysine. The content of threonine, glycine, isoleucine, lysine, and arginine varied in each component. The ratio of fucose, mannose, galactose, N-acetylgalactosamine, N-acetylglucosamine, and sialic acid of lactophorin, which contains about 18% saccharide, were 1, 6.6, 10.3, 5.5, 9.7, and 11.6, respectively, while the respective ratio of the seven components were 1, 5 to 6, 7 to 9, 3 to 4, 6 to 8, and 4 to 12. Sialic acid content varied in each component. Protein-carbohydrate linkage was N- and o-glucoside linkage. Lactophorin consisted of seven polypeptides (I to VII) with apparent molecular weights 17,000 to 67,000. Bands I, II, VI, and VII were glycoprotein. Bands VI and VII were major and had antigenicity to anti-soluble glycoprotein, while bands I to V were minor polypeptides. Component 1 consisted of only one polypeptide (VII), whereas the components 2 to 7 contained two major (VI, VII, or both) and several minor polypeptides. The sedimentation pattern of each component was a single and almost symmetrical peak. Sedimentation coefficient was 3.79 to 5.64 S and also varied in lactophorin. The results indicate that lactophorin has multiple forms.

Amino Acids↗
PubMed1989

Transfer of orally administered alpha-tocopherol into human milk.

The transfer of orally administered alpha-tocopherol (1.1 g) into breast milk reached a maximum value of 414 micrograms/100 g milk, which was 6.6-fold the pre-supplemental level, after three days and declined to the base line level after five days. The amount of alpha-tocopherol recovered in the milk was 0.11%. The alpha-tocopherol equivalent/PUFA ratio (mg/g) was increased from 0.25 to values between 0.7 and 1.7 by the administration.

Administration, Oral↗
PubMed1987

Accumulation of immunoreactive opsin on plasma membranes in degenerating rod cells of rd/rd mutant mice.

Immunoreactive opsin was detectable in the apical portion of normally developing photoreceptor cells on postnatal day 3 by the indirect enzyme-labeled antibody method. Immunoreactivity increased and had extended from the central retina to the periphery by the advanced stages of development. In the rd mutant retinas, accumulated opsin was present in the apical portion and in the outer nuclear layer on postnatal day 8. Immunoreactive opsin mainly was present in the outer nuclear layer by day 14, even being detectable on day 28. No immunoreactivity was present in the remaining cones. Electron microscopic immunocytochemistry confirmed the association of immunoreactive opsin with the persistent rod cell plasma membrane. Molecular weight of immunoreactive opsin in 14-day-old rd mutant mouse retina, as estimated by gel filtration chromatography, was large and did not seem to be degraded. These findings indicate that accumulated rhodopsin continues to function in the plasma membrane because an electroretinogram could be made after day 14 for the rd mutant mouse retina.

Animals↗
PubMed1979

Selective extraction of marker enzymes of bovine milk fat globule membrane by nonionic detergents.

Large amounts (66-97%) of marker enzymes such as alkaline phosphatase, 5'-nucleotidase, phosphodiesterase I, and gamma-glutamyl transpeptidase of bovine milk fat globule membrane (MFGM) were selectively solubilized by nonionic detergents such as Triton X-100, Tween 20, Nonidet P-40, Liponox NCK, and Emulgen 109-P. On the other hand, the extractability of MFGM protein with these detergents was less than 50%. Judging from the recovery of total activity, it is likely that alkaline phosphatase, phosphodiesterase I, and gamma-glutamyl transpeptidase are activated by nonionic detergents, whereas 5'-nucleotidase is somewhat inhibited by the detergents, except for Tween 20, and acid phosphatase is strongly inhibited by all detergents. In addition, solubilization of the protein with the nonionic detergents was found to be somewhat selective by SDS-polyacrylamide gel electrophoresis. There was no appreciable difference between the five brands of nonionic detergents used as regards the extractability of protein and the enzymatic activity of the extracted marker enzymes of MFGM, except that the solubilizing ability of Tween 20 was relatively low.

Acid Phosphatase↗
PubMed1975

Identification of alpha-, beta-, gamma-, and delta-tocopherols and their contents in human milk.

Human milk was found to contain naturally occuring beta-, gamma- and delta-tocopherol and gamma-tocotrienol in addition to alpha-tocopherol on thin-layer chromatography. Some of the tocopherols were also identified by gas-liquid chromatography and mass spectrometry. The mean content of alpha-, beta-, gamma- and delta-tocopherol was 319.3, 7.6, 23.9 and 4.9 mug/g lipid in twelve human colostra 52.5, 1.8, 10.2 and 2.3 mug/g lipid in three transitional milks and 61.7, 2.0, 9.2 and 1.1 mug/g lipid in three normal milks, respectively. A markedly high concentration of alpha-tocopherol was found in colostrum compared with transitional and normal human milk. Gamma-Tocotrienol was detected in colostrum as only one tocotrienol derivative on thin-layer chromatography. The importance of colostrum as the source of vitamin E for the newborn is suggested.

Chromatography, Gas↗
PubMedDate not supplied

Differential diagnosis of diffuse choroidal atrophies. Diffuse choriocapillaris atrophy, choroideremia, and gyrate atrophy of the choroid and retina.

Three young children showed a similar fundus appearance of sharply defined, yellowish-white, patchy or geographic atrophy of the retina and choroid and visible large choroidal vessels in almost the entire fundus. Fluorescein angiography disclosed atrophy of the retinal pigment epithelium and loss of choriocapillaris. Their visual functions and electrophysiologic findings were also similar. Family A was diagnosed as having diffuse choriocapillaris atrophy with autosomal dominant inheritance; family B, choroideremia with X-linked recessive heredity; and family C, gyrate atrophy of the choroid and retina with hyperornithinemia and autosomal recessive transmission. It became evident that diffuse choriocapillaris atrophy, choroideremia, and gyrate atrophy sometimes show a similar fundus appearance. Fluorescein angiography, serum ornithine levels, and family history were particularly helpful to differentiate these diffuse choroidal atrophies.

Adolescent↗