TABLE 3.

Characteristics of M. avium subsp. paratuberculosis MBP fusion proteins

Protein	Calculated mol size (Da)a	Amino acidsb	Antigenic indexc	Yieldd (mg/ml)
MBP-gene 250	21,434	199/199	Hydrophilic	0.2
MBP-gene 251	19,500	179/179	Hydrophilic	0.7
MBP-gene 252	9,687	96/96	Hydrophobic	2.0
MBP-gene 253	7,881	74/74	50/50	0.9
MBP-gene 254	16,262	146/141	50/50	1.3
MBP-gene 255	25,851	241/241	Hydrophilic	0.3
MBP-gene 256	15,120	141/141	Hydrophilic	0.1
MBP-gene 257	8,837	87/87	Hydrophilic	1.0
MBP-gene 240	21,734	194/163	Hydrophobic	0.4
MBP-gene 241	30,724	280/280	Hydrophilic	0.4
MBP-gene 228	40,817	369/216	Hydrophilic	0.6
MBP-gene 217	11,567	106/106	50/50	2.1
MBP-gene 218-C	91,530	835/365	Hydrophilic	1.4
MBP-gene 218-N	91,530	835/353	Hydrophilic	1.8
MBP-gene 219	10,004	87/85	Hydrophilic	0.04
MBP-gene 159	20,655	185/185	Hydrophobic	0.2
MBP-gene 135	17,018	157/141	Hydrophobic	1.0
MBP-gene 56	21,116	193/193	Hydrophilic	0.7
MBP-gene 57	25,485	252/252	50/50	1.4
MBP-gene 38	18,730	173/170	Hydrophilic	0.06
MBP-gene 10	36,380	322/205	Hydrophilic	0.8
MBP-gene 11	21,826	191/191	Hydrophilic	0.7

^aRepresents the calculated size of the entire predicted coding sequence but does not represent the size of the fusion protein.

^bTotal number of amino acids in predicted coding sequence/number of amino acids represented in the MBP fusion. In some instances, the mycobacterial protein of interest was truncated to minimize toxicity and/or enhance expression in E. coli.

^cThe hydrophilic nature of a protein is considered a crude estimate of the protein's antigenicity. M. paratuberculosis proteins were analyzed by Kyte-Doolittle hydropathy plots (20) using MacVector sequence analysis software. Proteins that were more than 60% hydrophilic were termed “hydrophilic,” proteins less than 40% hydrophilic were termed “hydrophobic,” and proteins displaying 40 to 60% hydrophilicity were termed “50/50.”

^dThe purification yield was determined by using a Bio-Rad protein assay on pooled fractions.