TY - JOUR
T1 - Thermodynamics of binding of the core trimannoside of asparagine-linked carbohyrates and deoxy analogs to Dioclea grandiflora lectin
AU - Dam, Tarun K.
AU - Oscarson, Stefan
AU - Brewer, C. Fred
PY - 1998/12/4
Y1 - 1998/12/4
N2 - The Man/Glc-specific seed lectin from Dioclea grandiflora (DGL) is a member of the Diocleinae subtribe that includes the jack bean lectin concanavalin A (ConA). Both DGL and ConA bind with high affinity to the 'core' trimannoside moiety, 3,6-di-O-(α-D-mannopyranosyl)-α-D- mannopyranoside, which is present in asparagine-linked carbohydrates. Recent hemagglutination inhibition studies suggest that DGL and ConA recognize similar epitopes of the trisaccharide but possess different binding specificities for complex carbohydrates (Gupta, D., Oscarson, S., Raju, T. S., Stanley, P., Toone, E. J., and Brewer, C. F. (1996) Eur. J. Biochem. 242, 320-326). In the present study, we have used isothermal titration microcalorimetry to determine the thermodynamics of binding of DGL to a complete set of monodeoxy analogs of the core trimannoside as well as a tetradeoxy analog. The thermodynamic data indicate that DGL recognizes the 2- , 3-, 4-, and 6-hydroxyl groups of the α(1,6) Man residue, the 3- and 4- hydroxyl group of the α(1,3) Man residue, and the 2- and 4-hydroxyl groups of the central Man residue of the trimannoside. The thermodynamic data for the tetradeoxy analog lacking the 3- and 4-hydroxyl group of the α(1,3) Man residue, and the 2- and 4-hydroxyl groups of the central Man residue of the trimannoside are consistent with the involvement of these hydroxyl groups in binding. While the overall pattern of data from DGL binding to the deoxy analogs is similar to that for ConA (Gupta, D., Dam, T. K., Oscarson, S., and Brewer, C. F. (1997) J. Biol. Chem. 272, 6388-6392), differences exist in the data for certain monodeoxy analogs binding to the two lectins. Differences are also observed in the thermodynamics of binding of DGL and ConA to a biantennary complex carbohydrate. In the following paper (Rozwarski, D. A., Swami, B. M., Brewer, C. F., and Sacchettini, J. C. (1998) J. Biol. Chem. 273, 32818-32825), the x-ray crystal structure of DGL complexed to the core trimannoside is presented, and a comparison is made of the thermodynamic binding data for DGL and ConA as well as the structures of their respective trimannoside complexes.
AB - The Man/Glc-specific seed lectin from Dioclea grandiflora (DGL) is a member of the Diocleinae subtribe that includes the jack bean lectin concanavalin A (ConA). Both DGL and ConA bind with high affinity to the 'core' trimannoside moiety, 3,6-di-O-(α-D-mannopyranosyl)-α-D- mannopyranoside, which is present in asparagine-linked carbohydrates. Recent hemagglutination inhibition studies suggest that DGL and ConA recognize similar epitopes of the trisaccharide but possess different binding specificities for complex carbohydrates (Gupta, D., Oscarson, S., Raju, T. S., Stanley, P., Toone, E. J., and Brewer, C. F. (1996) Eur. J. Biochem. 242, 320-326). In the present study, we have used isothermal titration microcalorimetry to determine the thermodynamics of binding of DGL to a complete set of monodeoxy analogs of the core trimannoside as well as a tetradeoxy analog. The thermodynamic data indicate that DGL recognizes the 2- , 3-, 4-, and 6-hydroxyl groups of the α(1,6) Man residue, the 3- and 4- hydroxyl group of the α(1,3) Man residue, and the 2- and 4-hydroxyl groups of the central Man residue of the trimannoside. The thermodynamic data for the tetradeoxy analog lacking the 3- and 4-hydroxyl group of the α(1,3) Man residue, and the 2- and 4-hydroxyl groups of the central Man residue of the trimannoside are consistent with the involvement of these hydroxyl groups in binding. While the overall pattern of data from DGL binding to the deoxy analogs is similar to that for ConA (Gupta, D., Dam, T. K., Oscarson, S., and Brewer, C. F. (1997) J. Biol. Chem. 272, 6388-6392), differences exist in the data for certain monodeoxy analogs binding to the two lectins. Differences are also observed in the thermodynamics of binding of DGL and ConA to a biantennary complex carbohydrate. In the following paper (Rozwarski, D. A., Swami, B. M., Brewer, C. F., and Sacchettini, J. C. (1998) J. Biol. Chem. 273, 32818-32825), the x-ray crystal structure of DGL complexed to the core trimannoside is presented, and a comparison is made of the thermodynamic binding data for DGL and ConA as well as the structures of their respective trimannoside complexes.
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U2 - 10.1074/jbc.273.49.32812
DO - 10.1074/jbc.273.49.32812
M3 - Article
C2 - 9830027
AN - SCOPUS:0032484122
SN - 0021-9258
VL - 273
SP - 32812
EP - 32817
JO - Journal of Biological Chemistry
JF - Journal of Biological Chemistry
IS - 49
ER -