A co-conserved gene pair supports iron homeostasis during chelation stress.

Unlabelled: Synthetic metal chelators are widely used in industrial, clinical, and agricultural settings, leading to their accumulation in the environment. We measured the growth of , a soil and aquatic bacterium, in the presence of the ubiquitous chelator ethylenediaminetetraacetic acid (EDTA) and found that it restricts growth by lowering intracellular iron levels. Using barcoded transposon sequencing, we identified an operonic gene pair, , that is required to maintain iron homeostasis in laboratory media during EDTA challenge.

Orthogonal Degron System for Controlled Protein Degradation in Cyanobacteria.

PCC 7942 is a model cyanobacterium for study of the circadian clock, photosynthesis, and bioproduction of chemicals, yet nearly 40% of its gene identities and functions remain unknown, in part due to limitations of the existing genetic toolkit. While classical techniques for the study of genes (, deletion or mutagenesis) can yield valuable information about the absence of a gene and its associated protein, there are limits to these approaches, particularly in the study of essential genes. Herein, we developed a tool for inducible degradation of target proteins in by adapting a method using degron tags from the transfer-mRNA (tmRNA) system.