Volume 88, no. 22, e01635-22, 2022, https://doi.org/10.1128/aem.01635-22. Figure 2A and B, Figure 6A and B, and the associated legends should appear as shown in this correction.
In response to an inquiry, we repeated specific experiments, namely, a subset of those shown in original Fig. 2 and 6. We confirmed that, as we previously reported, the single xds mutant retained a small amount of extracellular nuclease activity that could be attributed to dns. All strains behaved as shown in original Fig. 2A following growth of cells on DNase agar for 24 h, with robust halos for all strains that contained an intact xds gene and no halo for xds mutant strains (Fig. 2A). Also as previously reported, we observed halos on mucin plates for strains that contained an intact xds but no halo for the xds mutant or either of two xds dns double mutants at 24 h (Fig. 6).
We reported that the xds mutant produced a weak halo on DNase plates after prolonged incubation (72 h), and indeed, that was the basis for identifying dns as the responsible factor in the published work. In repeat experiments, we found that this slight ability was difficult to visualize at the 72 h time point and was more reliably observed at later times, such as after 6 days of incubation as shown in Fig. 2B, and on thin plates (e.g., 13 mL of media). This activity was dependent on dns, as a double mutant did not display that clear halo. This late (and weak) appearance of Dns-dependent activity is consistent with its importance in the cell aggregation phenotype that was assayed after 7 days in the original manuscript.
Despite this minor variation in the timing of measurable Dns activity, these results do not change any of the conclusions in the original publication, including our major conclusion that Xds is the predominant secreted nuclease in V. fischeri, while Dns plays a distinct role in a subset of tested phenotypes. Please see the Corrected and Republished paper (P. M. Fidopiastis, C. Childs, J. J. Esin, J. Stellern, A. Darin, A. Lorenzo, V. T. Mariscal, J. Lorenz, V. Gopan, S. McAnulty, and K. L. Visick, Appl Environ Microbiol e00328-24, 2024, https://doi.org/10.1128/aem.00328-24), in which we modified the text and replaced the figures. We also made corrections to the name of dns complement strain KV10273 (listed originally as KV10274) and to one of the primers used to construct it (primer 3352 was used rather than 4033 as originally listed).
| Strain | Genotype |
|---|---|
| ES114 | Wild type |
| KV7913 | xds::Tn5 |
| KV8811 | Δxds::FRT-erm |
| KV8865 | Δdns::FRT Δxds::FRT |
| KV9606 | Δdns::FRT |
| KV10273 | Δdns::FRT IG (yeiR-FRT-Erm/glmS)::PnrdR dns+ |
| KV10274 | pVSV105-xds/xds::Tn5 |
| KV10492 | xds::Tn5 Δdns::FRT |
Fig 2.
Nuclease activity of V. fischeri strains on DNase agar. (A) 24 h. Strains are as follows: ES114 (wild type), dns (KV9606), xds (KV7913), xds+ (KV10274), xds Δdns (KV10492), dns+ (KV10273). (B) 6 days. Strains are as follows: Δxds Δdns (KV8865), xds (KV7913), xds Δdns (KV10492), and Δxds (KV8811).
Fig 6.
Digestion of mucin at 24 h. (A) Strains are as follows: ES114 (wild type), dns (KV9606), xds (KV7913), dns+ (KV10273), xds+ (KV10274). (B) Strains are as follows: ES114 (wild type), xds Δdns (KV10492), Δxds Δdns (KV8865).