Search results
Results from the WOW.Com Content Network
A protein superfamily is the largest grouping of proteins for which common ancestry can be inferred (see homology). Usually this common ancestry is inferred from structural alignment [ 1 ] and mechanistic similarity, even if no sequence similarity is evident. [ 2 ]
In molecular biology, protein fold classes are broad categories of protein tertiary structure topology. They describe groups of proteins that share similar amino acid and secondary structure proportions. Each class contains multiple, independent protein superfamilies (i.e. are not necessarily evolutionarily related to one another). [1] [2] [3]
At the top level are all alpha proteins (domains consisting of alpha helices), all beta proteins (domains consisting of beta sheets), and mixed alpha helix/beta sheet proteins. While most proteins adopt a single stable fold, a few proteins can rapidly interconvert between one or more folds. These are referred to as metamorphic proteins. [5]
The study of proteins, generally under the heading of proteomics, is a vast and complex subject, and much effort has been made to classify and categorize, according to the many specific fields of investigation under which they come.
Protein domains allow protein classification by a combination of sequence, structure and function, and they can be combined in many ways. In an early study of 170,000 proteins, about two-thirds were assigned at least one domain, with larger proteins containing more domains (e.g. proteins larger than 600 amino acids having an average of more ...
SCOP2 prototype was a beta version of Structural classification of proteins and classification system that aimed to more the evolutionary complexity inherent in protein structure evolution. [12] It is therefore not a simple hierarchy, but a directed acyclic graph network connecting protein superfamilies representing structural and evolutionary ...
Submit a protein or DNA sequence for SCOP superfamily and family level classification using the SUPERFAMILY HMM's. Sequences can be submitted either by raw input or by uploading a file, but all must be in FASTA format. Sequences can be amino acids, a fixed frame nucleotide sequence, or all frames of a submitted nucleotide sequence.
A protein family is a group of evolutionarily related proteins. In many cases, a protein family has a corresponding gene family, in which each gene encodes a corresponding protein with a 1:1 relationship. The term "protein family" should not be confused with family as it is used in taxonomy.