Abstract
Type I toxin–antitoxin (TA) systems consist of a protein toxin that exerts a cytostatic or cytotoxic effect and an antisense RNA antitoxin that prevents translation of the toxin. Although well studied, type I TA systems have so far only been discovered in bacteria from the phyla Proteobacteria, Firmicutes, and Tenericutes. We hypothesized that type I systems could also be present in Cyanobacteria. Through bioinformatic analysis of the Microcystis aeruginosa PCC 7806SL genome, we discovered ten putative type I TA loci and characterized six of them experimentally. Two of the six putative type I toxins, BH695_0320 and MsoT1 (BH695_4017), were observed to negatively affect Escherichia coli cell growth, with MsoT1 exerting a phenotype similar to SrnB, a known type I toxin. We focused on the MsoT1/MsoA1 TA system and confirmed the expression of MsoT1 and MsoA1 in our assay. Additionally, we found that MsoA1 delays the toxic effects of MsoT1, indicating its role as a cognate antitoxin of MsoT1. Our results suggest that MsoT1/MsoA1 represents a novel candidate type I TA system, the first to be discovered in the Cyanobacteria phylum.
Keywords
sistemi toksin-antitoksin tipa I;cianobakterije;Microcystis aeruginosa;bakterijski toksini;novi sistemi toksin-antitoksin;type I toxin-antitoxin systems;cyanobacteria;bacterial toxins;novel toxin-antitoxin systems;
Data
| Language: |
English |
| Year of publishing: |
2025 |
| Typology: |
1.01 - Original Scientific Article |
| Organization: |
UL FKKT - Faculty of Chemistry and Chemical Technology |
| UDC: |
577:582.232 |
| COBISS: |
243643907
|
| ISSN: |
2072-6651 |
| Views: |
75 |
| Downloads: |
42 |
| Average score: |
0 (0 votes) |
| Metadata: |
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Other data
| Secondary language: |
Slovenian |
| Secondary keywords: |
sistemi toksin-antitoksin tipa I;cianobakterije;Microcystis aeruginosa;bakterijski toksini;novi sistemi toksin-antitoksin; |
| Type (COBISS): |
Article |
| Pages: |
str. 1-25 |
| Volume: |
ǂVol. ǂ17 |
| Issue: |
ǂiss. ǂ8, [article no.] 360 |
| Chronology: |
Aug. 2025 |
| DOI: |
10.3390/toxins17080360 |
| ID: |
26955613 |