*Review* **Current Knowledge on Microviridin from Cyanobacteria**

**Samuel Cavalcante do Amaral 1, Patrick Romano Monteiro 1,2, Joaquim da Silva Pinto Neto 1, Gustavo Marques Serra 1, Evonnildo Costa Gonçalves 2, Luciana Pereira Xavier <sup>1</sup> and Agenor Valadares Santos 1,\***


**Abstract:** Cyanobacteria are a rich source of secondary metabolites with a vast biotechnological potential. These compounds have intrigued the scientific community due their uniqueness and diversity, which is guaranteed by a rich enzymatic apparatus. The ribosomally synthesized and posttranslationally modified peptides (RiPPs) are among the most promising metabolite groups derived from cyanobacteria. They are interested in numerous biological and ecological processes, many of which are entirely unknown. Microviridins are among the most recognized class of ribosomal peptides formed by cyanobacteria. These oligopeptides are potent inhibitors of protease; thus, they can be used for drug development and the control of mosquitoes. They also play a key ecological role in the defense of cyanobacteria against microcrustaceans. The purpose of this review is to systematically identify the key characteristics of microviridins, including its chemical structure and biosynthesis, as well as its biotechnological and ecological significance.

**Keywords:** cyanobacteria; oligopeptide; microviridin; biotechnology; ecology

**Citation:** do Amaral, S.C.; Monteiro, P.R.; Neto, J.d.S.P.; Serra, G.M.; Gonçalves, E.C.; Xavier, L.P.; Santos, A.V. Current Knowledge on Microviridin from Cyanobacteria. *Mar. Drugs* **2021**, *19*, 17. https://doi.org/md19010017

Received: 17 November 2020 Accepted: 17 December 2020 Published: 4 January 2021

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