Registro Completo |
Biblioteca(s): |
Embrapa Caprinos e Ovinos. |
Data corrente: |
21/05/2024 |
Data da última atualização: |
21/05/2024 |
Autoria: |
GOLDFARB, M. |
Título: |
Two-dimensional electrophoresis and computer imaging: quantitation of human milk casein. |
Ano de publicação: |
1999 |
Fonte/Imprenta: |
Electrophoresis, v. 20, n. 4/5, p. 870-874, Apr-May, 1999. |
DOI: |
10.1002/(SICI)1522-2683(19990101)20:4/5<870::AID-ELPS870>3.0.CO;2-E. |
Idioma: |
Inglês |
Conteúdo: |
Abstract: Because human casein does not precipitate from milk at its isoelectric point as does bovine casein, there is no easy method of quantitation. Casein represents only approximately 30% of the protein fraction in human milk, and the complex methods necessary for isolation cannot be used easily with small samples in a survey of a large number of mothers. Two-dimensional electrophoresis coupled with computer imaging has the potential to compare and quantitate proteins expeditiously using a small sample size. Iso-Dalt, a denaturing methodology, separates the casein micelle into its component parts, beta-casein, kappa-casein, parakappa-casein and casomorphins. Identification of these spots was made by immunoassay of a Western blot with monoclonal anti-human casein. Two spots at 24 kDa and 26 kDa, thought to be phosphorylated isomers of beta casein, were selected for quantitation. Milk samples from 20 mothers, 8 weeks post partum, were run on two-dimensional (2-D) gels; a slide was taken of each silver-stained gel with a Kodak control strip; the slide was scanned into powerMac Photoshop 3 with a Polaroid-Sprintscan; spots were isolated using “threshold”, “mask” with IPTK (Imaging Processing Tool Kit, Reindeer Games) a Photoshop plug-in, and transferred to the NIH-Image program. Using an NIH-Image gel macro (Thomas Seebacher), the area and integrated density of the spots were measured. The Kodak control scale provided calibration and conversion to OD units. Visual scanning of the gels and computer units indicated a wide range of concentrations. To understand the range in units of weight, a standard was generated using bovine alpha casein (Sigma). Measurements will be used in a statistical program, Statview (Abacus), in an attempt to correlate information from a questionaire with casein concentration. MenosAbstract: Because human casein does not precipitate from milk at its isoelectric point as does bovine casein, there is no easy method of quantitation. Casein represents only approximately 30% of the protein fraction in human milk, and the complex methods necessary for isolation cannot be used easily with small samples in a survey of a large number of mothers. Two-dimensional electrophoresis coupled with computer imaging has the potential to compare and quantitate proteins expeditiously using a small sample size. Iso-Dalt, a denaturing methodology, separates the casein micelle into its component parts, beta-casein, kappa-casein, parakappa-casein and casomorphins. Identification of these spots was made by immunoassay of a Western blot with monoclonal anti-human casein. Two spots at 24 kDa and 26 kDa, thought to be phosphorylated isomers of beta casein, were selected for quantitation. Milk samples from 20 mothers, 8 weeks post partum, were run on two-dimensional (2-D) gels; a slide was taken of each silver-stained gel with a Kodak control strip; the slide was scanned into powerMac Photoshop 3 with a Polaroid-Sprintscan; spots were isolated using “threshold”, “mask” with IPTK (Imaging Processing Tool Kit, Reindeer Games) a Photoshop plug-in, and transferred to the NIH-Image program. Using an NIH-Image gel macro (Thomas Seebacher), the area and integrated density of the spots were measured. The Kodak control scale provided calibration and conversion to OD units. Visual scanning o... Mostrar Tudo |
Palavras-Chave: |
Computer imaging. |
Thesaurus Nal: |
Casein; Humans; Milk; Two-dimensional gel electrophoresis; Western blotting. |
Categoria do assunto: |
-- |
Marc: |
LEADER 02510naa a2200205 a 4500 001 2164387 005 2024-05-21 008 1999 bl uuuu u00u1 u #d 024 7 $a10.1002/(SICI)1522-2683(19990101)20:4/5<870::AID-ELPS870>3.0.CO;2-E.$2DOI 100 1 $aGOLDFARB, M. 245 $aTwo-dimensional electrophoresis and computer imaging$bquantitation of human milk casein.$h[electronic resource] 260 $c1999 520 $aAbstract: Because human casein does not precipitate from milk at its isoelectric point as does bovine casein, there is no easy method of quantitation. Casein represents only approximately 30% of the protein fraction in human milk, and the complex methods necessary for isolation cannot be used easily with small samples in a survey of a large number of mothers. Two-dimensional electrophoresis coupled with computer imaging has the potential to compare and quantitate proteins expeditiously using a small sample size. Iso-Dalt, a denaturing methodology, separates the casein micelle into its component parts, beta-casein, kappa-casein, parakappa-casein and casomorphins. Identification of these spots was made by immunoassay of a Western blot with monoclonal anti-human casein. Two spots at 24 kDa and 26 kDa, thought to be phosphorylated isomers of beta casein, were selected for quantitation. Milk samples from 20 mothers, 8 weeks post partum, were run on two-dimensional (2-D) gels; a slide was taken of each silver-stained gel with a Kodak control strip; the slide was scanned into powerMac Photoshop 3 with a Polaroid-Sprintscan; spots were isolated using “threshold”, “mask” with IPTK (Imaging Processing Tool Kit, Reindeer Games) a Photoshop plug-in, and transferred to the NIH-Image program. Using an NIH-Image gel macro (Thomas Seebacher), the area and integrated density of the spots were measured. The Kodak control scale provided calibration and conversion to OD units. Visual scanning of the gels and computer units indicated a wide range of concentrations. To understand the range in units of weight, a standard was generated using bovine alpha casein (Sigma). Measurements will be used in a statistical program, Statview (Abacus), in an attempt to correlate information from a questionaire with casein concentration. 650 $aCasein 650 $aHumans 650 $aMilk 650 $aTwo-dimensional gel electrophoresis 650 $aWestern blotting 653 $aComputer imaging 773 $tElectrophoresis$gv. 20, n. 4/5, p. 870-874, Apr-May, 1999.
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Registro original: |
Embrapa Caprinos e Ovinos (CNPC) |
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