All chemicals and enzymes used were purchased from Sigma-Aldrich or Fisher Scientific unless noted otherwise. Endoproteinase Glu-C was purchased from Worthington Biosciences. UDP-xylose was obtained from Complex Carbohydrate Research Center. Oligonucleotide primers used for molecular cloning were purchased from Integrated DNA Technologies. Phusion High-Fidelity DNA polymerase, Q5 DNA polymerase, Taq ligase, dNTP solutions, T4 DNA ligase, and all restriction endonucleases were purchased from New England BioLabs. Gel extraction, plasmid miniprep, and PCR purification kits were purchased from QIAGEN. Protein Calibration Standard I and Peptide Calibration Standard II for MALDI–TOF MS were purchased from Bruker. E. coli NEB Turbo was used as host for cloning and plasmid propagation, and E. coli BL21(DE3) SHuffle was used as a host for expression of deglycosublancin.19 (link) Nickel resin used for gravity-based purification of His-tagged peptides or proteins was purchased from Takara Biosciences. Gradient gels used for checking protein expression were purchased from Biorad Inc. Plasmids pHCMC04 and pJOE8999 for molecular cloning in B. subtilis Δspβ were purchased from the Bacillus Genetics Stock Center (BGSC). B. subtilis Δ6 and plasmids encoding fluorescent proteins in Bacillus were also purchased from BGSC. Cyanine-5-amine was purchased from Lumiprobe.