. Author manuscript; available in PMC: 2018 Mar 29.

Published in final edited form as: J Am Chem Soc. 2017 Mar 21;139(12):4310–4313. doi: 10.1021/jacs.7b00693

Table 1.

TbtA precursor peptide variants tested for methylation by TbtI. TbtA sequence: Leader-SCNCFCYICCSCSSA

Variant	Outcome
wild-type hexazole	Fully processed
wild-type hexazole core (three res. leader)	Fully processed
C4A pentazole	Not processed
C4S pentazole	Not processed
N3A hexazole	Not processed
N3D hexazole	Not processed
N3Q hexazole	Not processed
S1N/C4A pentazole	Not processed
C4A/F5N pentazole	Not processed
C4A/I8N pentazole	Not processed
C4A/S11N pentazole	Not processed
Cys4 monoazole	Not processed
Cys2/4 diazole	Not processed
Cys4/6 diazole	Fully processed
Cys4/9 diazole	Partially processed
Cys4/10 diazole	Not processed
Cys4/12 diazole	Not processed
S1N/N3Fhexazole	Not processed