Related Experiment Video
Updated: Jul 25, 2026
10:59
Enrichment of Bacterial Lipoproteins and Preparation of N-terminal Lipopeptides for Structural Determination by Mass Spectrometry
Published on: May 21, 2018
The lipocalin protein family: structural and sequence overview
D R Flower1, A C North, C E Sansom
1The Edward Jenner Institute for Vaccine Research, Newbury, Berkshire, UK. darren.flower@jenner.ac.uk
Biochimica Et Biophysica Acta
|November 4, 2000
Summary
Lipocalins exhibit diverse sequences but conserved structures, classified as kernel or outlier types. They belong to the calycins superfamily, sharing a common beta-barrel structure and signature.
Area of Science:
- Biochemistry
- Structural Biology
- Protein Science
Background:
- Lipocalins display significant sequence diversity.
- Lipocalins possess highly conserved structural features.
- Classification into kernel and outlier lipocalins aids family analysis.
Purpose of the Study:
- To analyze the sequence and structural diversity of lipocalins.
- To understand the relationship between lipocalins and the broader calycins superfamily.
- To identify conserved structural signatures within the calycins superfamily.
Main Methods:
- Sequence analysis to classify lipocalins.
- Structural analysis to identify conserved motifs.
- Comparative analysis with related protein families within the calycins superfamily.
Main Results:
- Lipocalins are classified into kernel (three motifs) and outlier (one or two motifs) groups.
- Smaller, highly similar sequence groups exist within these classifications.
- Lipocalins are part of the calycins superfamily, characterized by a conserved beta-barrel structure and signature.
Conclusions:
- The classification system effectively organizes lipocalin diversity.
- The calycins superfamily shares a common structural fold and signature.
- Structural conservation underlies the functional diversity of lipocalins.
Related Concept Videos
03:38Structure of Lipids
Lipids include a diverse group of compounds that are largely nonpolar in nature. This is because they are hydrocarbons that include mostly nonpolar carbon-carbon or carbon-hydrogen bonds. Non-polar molecules are hydrophobic (“water fearing”), or insoluble in water. Lipids perform many different functions in a cell. Cells store energy for long-term use in the form of fats. Lipids also provide insulation from the environment for plants and animals. For example, they help keep aquatic birds and...
03:38Structure of Lipids
Lipids include a diverse group of compounds that are largely nonpolar in nature. This is because they are hydrocarbons that include mostly nonpolar carbon-carbon or carbon-hydrogen bonds. Non-polar molecules are hydrophobic (“water fearing”), or insoluble in water. Lipids perform many different functions in a cell. Cells store energy for long-term use in the form of fats. Lipids also provide insulation from the environment for plants and animals. For example, they help keep aquatic birds and...
02:47Protein Families
Protein families are groups of homologous proteins; that is, they have similarities in amino acid sequences and three-dimensional structures. Protein families usually occur because of gene duplication, where an additional copy of a gene is inserted into the genome of an organism. Mutations that change the amino acids but still allow the protein to be properly synthesized, will lead to new protein family members. If these new proteins contain similar amino acids in key locations, protein...
02:47Protein Families
Protein families are groups of homologous proteins; that is, they have similarities in amino acid sequences and three-dimensional structures. Protein families usually occur because of gene duplication, where an additional copy of a gene is inserted into the genome of an organism. Mutations that change the amino acids but still allow the protein to be properly synthesized, will lead to new protein family members. If these new proteins contain similar amino acids in key locations, protein...
03:38Structure of Lipids
Lipids include a diverse group of compounds that are largely nonpolar in nature. This is because they are hydrocarbons that include mostly nonpolar carbon-carbon or carbon-hydrogen bonds. Non-polar molecules are hydrophobic (“water fearing”), or insoluble in water. Lipids perform many different functions in a cell. Cells store energy for long-term use in the form of fats. Lipids also provide insulation from the environment for plants and animals. For example, they help keep aquatic birds and...
01:19Formation of Lipopolysaccharides
Lipopolysaccharides (LPS) are crucial components of the outer membrane of Gram-negative bacteria, serving both structural and functional roles. It contributes to membrane stability and protects bacteria from host immune responses. LPS is composed of three major regions—lipid A, a core oligosaccharide, and an O antigen. The biosynthesis and assembly of LPS involve a highly coordinated set of enzymatic reactions and transport mechanisms. Additionally, LPS is recognized as an endotoxin, triggering...