Research
| Title： | Discovery of two natural strains closely similar to the model strain Anabaena sp. PCC 7120 used in molecular studies of heterocyst differentiation |
|---|---|
| First author： | Hu, Xi; Wang, Weipeng; Wang, Yali; Ning, Degang; Xu, Xudong |
| Journal： | JOURNAL OF OCEANOLOGY AND LIMNOLOGY |
| Years： | 2025 |
| DOI： | 10.1007/s00343-025-5149-2 |
| Abstract： | Microevolution of commonly used model bacterial strains may lead to inconsistent genetic analysis results across laboratories. To address this issue, it is helpful to introduce a verification strain that belongs to the same species as the model strain. Anabaena sp. PCC 7120 is the model cyanobacterial strain for studies of heterocyst differentiation, and inconsistent results produced with different substrains have been reported. Novel Anabaena isolates outside PCC 7120 and derivatives are needed for verification on analysis results. We report that two Anabaena strains independently isolated from natural environments, FACHB-595 and FACHB-709, are nearly identical to Anabaena sp. PCC 7120 in genome sequence (hundreds of SNPs, indels, insertions/deletions), except for the changes in two of the six plasmids in one of the strains. We deleted genes involved in heterocyst differentiation and pattern formation-including hetR, hetZ, hetP, hetC, patS, patU3, patX, patL, and patA-in the two new strains and observed phenotypes consistent with previous reports; in mutants of nrrA or patN, however, we found accelerated or delayed heterocyst formation compared to the reports. Therefore, both FACHB-595 and FACHB-709 can serve as strains to verify the genetic analyses conducted using Anabaena sp. PCC 7120. |
