Conserved Site

Small acid-soluble spore protein, alpha/beta-type, conserved site (IPR018126)

Short name: SASP_alpha/beta-type_CS


Small, acid-soluble spore proteins (SASP or ASSP) are proteins bound to the spore DNA of bacteria of the genera Bacillus, Thermoactynomycetes, and Clostridium [PMID: 3059997, PMID: 1569005]. They are double-stranded DNA-binding proteins that cause DNA to change to an A-like conformation. They protect the DNA backbone from chemical and enzymatic cleavage and are thus involved in dormant spore's high resistance to UV light. SASP are degraded in the first minutes of spore germination and provide amino acids for both new protein synthesis and metabolism.

There are two distinct families of SASP: the alpha/beta type and the gamma-type. Alpha/beta SASP are small proteins of about sixty to seventy amino acid residues that are generally coded by a multigene family. The N terminus of alpha/beta SASP contains the site which is cleaved by a SASP-specific protease that acts during germination while the C terminus and is probably involved in DNA-binding.

GO terms

Biological Process

GO:0006265 DNA topological change

Molecular Function

GO:0003690 double-stranded DNA binding

Cellular Component

No terms assigned in this category.

Contributing signatures

Signatures from InterPro member databases are used to construct an entry.
PROSITE patterns
PROSITE patterns