REAGENT or RESOURCE	SOURCE	IDENTIFIER
Bacterial and Virus Strains
E. coli NEB5α	NEB	Cat#C2987
E. coli BL21 (DE3) Gold	Agilent	Cat#230132
E. coli BW25113	Dr. Kirill A. Datsenko, Purdue University	Datsenko and Wanner, 2000
E. coli BW25113 tldD-	Host lab	Ghilarov et al., 2017
Chemicals, Peptides, and Recombinant Proteins
Gel Filtration HMW Calibration Kit	GE Healthcare	Cat#28403842
TEV protease	Host lab stocks	N/A
TldD/E protease	Host lab stocks	Ghilarov et al., 2017
HisTrap FF	GE Healthcare	Cat#17531901
HiTrap Chelating HP	GE Healthcare	Cat#17040801
Superdex 200 Increase 10/300	GE Healthcare	Cat#28990944
Superdex 200 Increase 5/150	GE Healthcare	Cat#28990945
MBPTrap HP 1ml	GE Healthcare	Cat#29048641
Critical Commercial Assays
Gel Extraction and DNA Cleanup Micro Kit	Thermo Scientific	Cat#K0832
GeneJET Plasmid Miniprep Kit	Thermo Scientific	Cat#K0503
Phusion High-Fidelity PCR Kit	Thermo Scientific	Cat#F553S
Deposited Data
BCD-pB17-ADP-P (McbBCD complexed with processed McbA, ADP and phosphate)	RCSB PDB	6GRG
BCD-pB17 (McbBCD complexed with fully processed McbA)	RCSB PDB	6GOS
BCD-pB17short (McbBCD complexed with fully processed McbA 1–46)	RCSB PDB	6GRH
BCD-free (apo McbBCD)	RCSB PDB	6GRI
Oligonucleotides
Described in Table S2		N/A
Recombinant DNA
pBAD/His B	Thermo (Invitrogen)	V43001
pBAD Ec-McB	Dr. Mikhail Metelev, Uppsala University	Metelev et al., 2013
pBAD Ec-McB-His	This work	N/A
pBAD Ec-McB-His 1-46	This work	N/A
pBAD mcbBCD and mutants used in the study	This work	N/A
pET28-MBP mcbA	Host lab	Ghilarov et al., 2017
pET28-MBP mcbA mutants used in the study	This work	N/A
Software and Algorithms
XDS	http://www.ccp4.ac.uk/	Kabsch, 2010
AIMLESS	http://www.ccp4.ac.uk/	Evans and Murshudov, 2013
XIA2	http://www.ccp4.ac.uk/	Winter, 2010
BUCCANEER	http://www.ccp4.ac.uk/	Cowtan, 2006
CRANK2	http://www.ccp4.ac.uk/	Skubák and Pannu, 2013
SHELX	http://www.ccp4.ac.uk/	Sheldrick, 2008
REFMAC5	http://www.ccp4.ac.uk/	Murshudov et al., 1997
MOLPROBITY	http://www.ccp4.ac.uk/	Davis et al., 2007
COOT	http://www.ccp4.ac.uk/	Emsley and Cowtan, 2004
CCP4MG	http://www.ccp4.ac.uk/	McNicholas et al., 2011
Other
LithoLoops 0.02 mm	Molecular Dimensions	MD7-130
SeedBead Kit PTFE	Hampton Research	HR2-320
96 well MRC crystallization plates	Molecular Dimensions	MD11-00-100
Amicon concentrators 30 kDa cutoff	Millipore	UFC903024
C18 Zip-Tips	Milllipore	ZTC18S096