Two Foreign Antimicrobial Peptides Expressed in the Chloroplast of Porphyridium purpureum Possessed Antibacterial Properties

Abstract

To solve the problem of antibiotic abuse in aquaculture and to utilize the application potential of antimicrobial peptides (AMPs), a chloroplast transformation system of Porphyridium purpureum was successfully constructed for effectively expressing two exogenous AMPs. The endogenous fragments of 16S rDNA/trnA-23S rDNA were used as flanking fragments for the homologous recombination in the chloroplast genome. Two AMPs encoded by the transformation vector were controlled by the native promoter psbB in a polycistron. The plasmids were transferred into P. purpureum via particle bombardment and the transformation vectors were screened using phosphinothricin (bar), a dominant selection marker under the control of the psbA promoter. Subsequently, in the positive transformed colonies, the exogenous fragments were found to be inserted in the flanking fragments directionally as expected and two foreign AMPs were successfully obtained. Finally, two exogenous peptides with antibacterial properties were obtained from the transformed strain. The two AMPs expressed by the transformed strain were shown to have similar inhibitory effects to antibiotics by inhibition tests. This suggested that AMPs can be introduced into aquaculture using baited microalgae, providing new ideas and ways to solve a series of aquaculture diseases caused by bacteria.

Study of the Antimicrobial Potential of the Arthrospira platensis, Planktothrix agardhii, Leptolyngbya cf. ectocarpi, Roholtiella mixta nov., Tetraselmis viridis, and Nanofrustulum shiloi against Gram-Positive, Gram-Negative Bacteria, and Mycobacteria

“…With their capacity to fend off and defend against diseases, cyanobacteria and microalgae are valuable sources of such compounds [ 23 ]. Alkaloids, fatty acids, indoles, macrolides, peptides, phenols, pigments, and terpenes are some of the antibacterial substances created by cyanobacteria [ 24 , 25 ]. The kind of algae, the extractor, and the concentration of the extract all affect the antibacterial potential of cyanobacteria, macro-, and microalgae [ 26 ].…”

In Vitro study of the nutritional and pharmacological contribution of Pennisetum purpureum Schumach leaves: Natural food used by guinea pig (Cavia porcellus) breeders in Gabon

“…The genus Pennisetum contains remarkable natural bioactive components and is frequently used for therapeutic purposes such as the treatment of dysentery, fever, diabetes and abdominal pain (Ojo et al, 2022). Previous studies have shown that P. purpureum has some biological (Ujang et al, 2021;Han et al, 2022) and digestibility properties (Wahyono et al, 2022). Very few studies have been carried out on the anti-inflammatory, antioxidant and antimicrobial activities of P. purpureum leaves.…”