UMMS Affiliation

Department of Molecular Genetics and Microbiology; Department of Microbiology and Physiological Systems

Publication Date


Document Type



Bacteriology | Microbiology | Physiology


The major acid-soluble spore proteins (ASSPs) isolated from mature spores of Bacillus subtilis are designated alpha, beta, and gamma (about 60, 60, and 100 amino acids in length, respectively). Alpha and beta are very similar, and gamma is very similar to a less predominant ASSP called delta (about 115 amino acids). A minor and very basic ASSP called epsilon is the same size as alpha and beta but is unrelated antigenically. These and several minor ASSPs comprise at least three related families of sporulation-specific gene products. Expression of the alpha and beta genes, detectable as functional mRNA in vitro, coincides with the time of synthesis of all of the major ASSPs in vivo. This apparently coordinate expression is dependent on at least the spo0A, spoIIA, and spoIIIA loci, but not on the spoIVA or spoVA loci, consistent with the late stage of this expression (initiating at 3.5 h after the start of sporulation and peaking at 5 h after start of sporulation). A few minor ASSPs may be asynchronously expressed.


acid-soluble spore proteins (ASSPs), Bacillus subtilis

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Copyright © 1985, American Society for Microbiology. Publisher PDF posted as allowed by the publisher's copyright policy at


J Bacteriol. 1985 Aug;163(2):543-51. Link to article on publisher's site

Journal/Book/Conference Title

Journal of bacteriology

Related Resources

Link to Article in PubMed

PubMed ID