Arylomycin analogs are provided, wherein the analogs can have broad spectrum bioactivity. Resistance to the antibiotic bioactivity of natural product arylomycin in a range of pathogenic bacterial species has been found to depend upon single amino acid mutations at defined positions of bacterial Signal Peptidases (SPases), wherein the presence of a proline residue confers arylomycin resistance. Arylomycin analogs are provided herein that can overcome that resistance and provide for a broader spectrum of antibiotic bioactivity than can natural product arylomycins such as arylomycin A2. Methods for determining if a bacterial strain is susceptible to narrow spectrum arylomycin antibiotics, or if a broad spectrum analog is required for treatment, is provided. Pharmaceutical compositions and methods of treatment of bacterial infections, and methods of synthesis of arylomycin analogs, are provided.