{{tag>structure}}
====== Class =======

This is the highest level of classification and is derived from the gross secondary structure
content. There are 4 classes defined in the CATH classification.

  -  Mainly Alpha
  -  Mainly Beta
  -  Alpha Beta
  -  Few Secondary Structures.

The classification of protein domains into these 4 classes has been achieved for 90% of
structures automatically, using an automated class assignment protocol. This classification protocol includes a number of criteria:

  * Percentage composition of secondary structures
  * Percentage of secondary structures contacts
  * Secondary structure alternation
  * Percentage of parallel strands

This is discussed in detail in the paper referenced below.


===== References =====

{{pubmed>long:8831787}}