Synechococcus elongatus is a cyanobacterium (see cyanobacteriia) analysed in the corpus’s gene-fitness projects 1. Reports refer to it by the alias SynE 2,3,4.
Metal sensitivity
In the metal-fitness-atlas, 3.3% of all gene × metal records (12,838 / 383,349) show significant fitness defects (fit < -1, |t| > 4). Within that atlas, SynE is described as notably metal-sensitive, with 33.6% of genes important across just 2 metals. By comparison, desulfovibrio-vulgaris-hildenborough (DvH) has 1,366 metal-important genes (49.8% of its genome across 13 metals). The SynE figure covers only 2 metals, compared with 13 for DvH. It should therefore be read as a result for one organism with narrow metal coverage 1.
NaCl dose-response outlier
SynE has 12 sodium chloride (NaCl) dose-response experiments spanning 0.5–250 mM, far more than any other organism (1–6 NaCl experiments). It is a dramatic outlier in the metal–NaCl comparison, at 88.6% shared-stress (565/638 genes) 3,4,2.
This outlier status is a recorded pitfall. Using n_sick >= 1 (at least one NaCl experiment with fit < -1) as an NaCl-importance threshold is biased by the number of NaCl experiments per organism, and the threshold is much easier to satisfy with 12 experiments. Under it, SynE flags 32.6% of genes as NaCl-important, 3× higher than the next organism, which inflates cross-condition overlap statistics 2,3,4.
Sensitivity check: excluding SynE, overall metal–NaCl overlap drops from 39.8% to 36.7% (3,739/10,183). The project describes this as a modest drop that confirms the pooled finding is not driven by this outlier 3,4,2. The next-highest organisms (Korea 58.6%, Phaeo 56.4%, Pedo557 53.0%) have typical NaCl experiment counts 3. When comparing conditions with unequal experiment counts, the recommended mitigation is either to require n_sick >= 2 or use mean_fit < threshold instead of n_sick >= 1, or to report results with and without outlier organisms. This feeds shared-stress-versus-stressor-specific-fitness 2.