Fig. 4. Genetic characterization of the genes for TXN biosynthesis in vivo. HPLC analysis of TXN-A and analogues production (UV at 271 nm) from S. bottropensis: (I) wild-type NRRL 12051, (A-II) mutant TG5001 (ΔtxnA1), (A-III) TG5002 (Δorf–3), (A-IV) TG5003 (Δorf–1), (A-V) TG5004 (ΔtxnRg1), (A-VI) TG5005 (Δorf+11), (A-VII) TG5006 (Δorf+3), (A-VIII) TG5007 (ΔtxnRg6), (A-VIV) TG5008 (ΔtxnA4); (B-II) TG5009 (ΔtxnC2), (B-III) TG5010 (ΔtxnC4), (B-IV) TG5011 (ΔtxnC3), (B-V) TG5012 (ΔtxnO2), (B-VI) TG5013 (ΔtxnO5), (B-VII) TG5014 (ΔtxnO6), (B-VIII) TG5015 (ΔtxnO12), (B-VIV) TG5016 (ΔtxnB4). () TXN-A. The genotypes of all the mutants were confirmed by PCR analysis, and the results were summarized in Fig. S2.† .