TABLE 1.

CBS activities of WT and selected mutants in E. coli crude extracts after expression in the absence or presence of three chemical chaperones

CBS activities are expressed in percent relative to CBS activity of the WT expressed in the absence of a chaperone representing 100%. The average activity of WT CBS expressed from pGEX-6P1-hCBS construct in E. coli Rosetta2 (DE3) crude extract was 402 ± 86 milliunits/mg of protein. Values represent average values with S.E. from at least three measurements. The bold values denote the conditions, which were subsequently used for the large-scale expression and protein purification of each mutant.

CBS protein	CBS activity (% of WT)
	No chaperone	1% ethanol	3% ethanol	1 mm TMAO	10 mm TMAO	100 mm TMAO	1% DMSO	3% DMSO	6% DMSO
WT	100	130 ± 15	171 ± 31	89 ± 14	94 ± 6	82 ± 7	106 ± 19	160 ± 14	166 ± 25
P49L	91 ± 5	161 ± 22	241 ± 25	114 ± 17	123 ± 10	177 ± 24	115 ± 17	154 ± 11	254 ± 21
P78R	51 ± 8	89 ± 12	60 ± 4	56 ± 8	60 ± 5	55 ± 11	60 ± 12	77 ± 5	58 ± 4
A114V	43 ± 4	115 ± 13	137 ± 12	68 ± 6	77 ± 6	77 ± 4	72 ± 6	110 ± 15	62 ± 8
R125Q	11 ± 5	59 ± 7	29 ± 3	103 ± 4	97 ± 6	87 ± 12	103 ± 10	79 ± 7	49 ± 5
E176K	21 ± 2	57 ± 8	47 ± 8	32 ± 6	34 ± 4	42 ± 3	34 ± 5	43 ± 11	27 ± 4
P422L	125 ± 13	279 ± 45	433 ± 65	135 ± 11	154 ± 17	221 ± 35	295 ± 18	299 ± 36	348 ± 52
I435T	426 ± 51	855 ± 71	1001 ± 21	287 ± 42	139 ± 20	531 ± 44	160 ± 13	557 ± 27	505 ± 31
S466L	828 ± 63	933 ± 34	1063 ± 32	760 ± 37	755 ± 64	990 ± 51	816 ± 76	976 ± 65	1119 ± 79