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Updated: Aug 10, 2026

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Chemically-blocked Antibody Microarray for Multiplexed High-throughput Profiling of Specific Protein Glycosylation in Complex Samples
Published on: May 4, 2012
Summary
Researchers purified rabbit alpha-lactalbumin, revealing it as a glycoprotein with a unique C-terminus. Sequence analysis suggests accelerated evolution of the alpha-lactalbumin gene.
Area of Science:
- Biochemistry
- Molecular Biology
- Genetics
Background:
- Alpha-lactalbumin is a key whey protein found in milk.
- Understanding its structure and evolution provides insights into protein function and gene regulation.
Purpose of the Study:
- To purify and characterize rabbit alpha-lactalbumin.
- To determine its amino acid sequence and glycosylation.
- To investigate evolutionary aspects of the alpha-lactalbumin gene.
Main Methods:
- Purification of alpha-lactalbumin from New Zealand White rabbit milk.
- Amino acid sequencing using sequenator analysis and carboxypeptidase digestion.
- Preparative peptide mapping utilizing 2,5-diphenyloxazole (PPO) fluorescence detection.
Main Results:
- Rabbit alpha-lactalbumin is predominantly a glycoprotein with 5 mol glucosamine/mol protein.
- The protein comprises 122 amino acids with a single carbohydrate moiety likely at Asn-45.
- Rabbit alpha-lactalbumin's C-terminus is one residue shorter than other known variants.
- Sequence comparisons suggest a higher mutation rate in the alpha-lactalbumin gene than previously assumed.
Conclusions:
- Rabbit alpha-lactalbumin exhibits distinct structural features, including glycosylation and a truncated C-terminus.
- The alpha-lactalbumin gene appears to evolve more rapidly than anticipated.
- A novel peptide mapping technique enhances preparative analysis.
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