Functional characterization of oligopeptide transporter 1 of dairy cows

Table 1 Kinetic parameters of CHO cells transfected with bovine, sheep, pig, and chicken PepT1 cDNA

Substrate	Molecular weight	Charge^a	Hydrop-hobicity^b	pI	IC₅₀, mmol/L
Substrate	Molecular weight	Charge^a	Hydrop-hobicity^b	pI	Bovine	Sheep^c	Pig^d	Chicken^e
Gly-Lys	203	Positive	3.3	10.1	0.078	ND	ND	ND
Gly-Met	206	Neutral	1.5	5.5	0.032	ND	0.03	0.07
Lys-Lys	274	Positive	−7.8	10.0	9.649	0.739	3.8	7.9
Lys-Met	277	Positive	−2.0	8.8	0.032	0.051	0.04	0.11
Lys-Phe	293	Positive	−1.1	8.8	0.090	0.024	0.03	0.11
Met-Glu	278	Negative	−1.6	4.6	0.023	0.037	0.53	0.02
Met-Gly	206	Neutral	1.5	5.3	0.058	0.016	0.008	0.27
Met-Leu	262	Neutral	5.7	5.3	0.080	0.021	0.004	0.04
Met-Lys	277	Positive	−2.0	8.5	0.020	0.123	ND	0.07
Met-Met	280	Neutral	3.8	5.3	0.096	0.024	0.013	0.02
Trp-Phe	351	Neutral	1.9	5.5	0.014	ND	0.06	0.02
Leu-Gly-Gly	245	Neutral	3.0	5.5	2.069	0.127	0.27	0.08
Lys-Trp-Lys	460	Positive	−8.7	10.0	CBD	3.732	2.2	5.9
Met-Leu-Phe	409	Neutral	8.5	5.3	0.050	0.014	0.4	0.04
Met-Gly-Met-Met	468	Neutral	5.3	5.3	6.043	0.952	CBD	3.9

pI isoelectric point, calculated using pK values of the constituent amino acids, IC₅₀ 50% inhibitory concentration, ND not determined; CBD cannot be determined
^a Charge was calculated at pH 6.0
^b Hydrophobicity was calculated as the average of the value of the constituent amino acids according to Kyte and Doolittle [38]
^c Sheep PepT1 data from Chen et al. [14]
^d Pig PepT1 data from Klang et al. [17]
^e Chicken PepT1 data from Chen et al. [15]

ISSN: 2049-1891