Patellamide A is a peptide natural product produced by Prochloron didemni, a cyanobacterial symbiont of Lissoclinum patella, and was first isolated in 1981.

The patellamides and trunkamide show moderate cytotoxicity and activity against multidrug resistant cancer cell lines.

[4] Patellamide A originates from a ribosomal peptide, making it a member of the RiPP superfamily of natural products.

This was determined after genome sequencing of P. didemi showed a lack of non ribosomal peptide synthetases.

The gene patE encodes the precursor peptide that contains the primary sequences of patellamides A and C. It has been proposed by Schmidt et al. that this prepatellamide is heterocyclized to form the oxazoline and thiazoline rings by PatD2.