Fur family transcriptional regulators and their genomic context in A) Acidithiobacilli, B) Leptospirilla. Color coding indicates orthology and bars linking genes through genomes indicate percentage of amino acid sequence similarity. AT: A. thiooxidans. AF: A. ferrooxidans. AC: A. caldus. LIIa: Leptospirillum sp. Group II UBA. LIIb: Leptospirillum sp. Group II 5-way GC. LIII: Leptospirillum sp. Group III 5-way GC.