Oxidized Raffinose Intramolecular
Cross-linking of Porcine Hemoglobin：
Effects on Its Structure and Function
HONG Min, LI Shi-Yun and YUAN Zhong-Yi*
( Shanghai Institute of Biochemistry, the Chinese Academy of Sciences,
Shanghai 200031, China )
Abstract Periodate-oxidized raffinose
is utilized to modify porcine oxyhemoglobin and deoxyhemoglobin, respectively.
These modified protein derivatives showed special characteristics that it can
resist the dissociation of α2β2 tetramer in
comparison with natural proteins. According to the analysis in SDS-PAGE and
reverse phase HPLC, the two porcine hemoglobin derivatives are all
intramolecular linked proteins and the cross-linking sites lie between the two β
subunits. No eminent differences were found in the UV-VIS absorption spectrum
between natural and modified proteins. However, after calibration for protein
concentration, the emission of modified porcine deoxyhemoglobin is much weaker
than the modified oxyhemoglobin and the natural protein. Furthermore, the
porcine hemoglobin derivatives’ characteristics of the oxygen affinity and
Auto-oxidized rate also show significant differences with natural protein. The
possible application of these porcine hemoglobin derivatives in the preparation
of hemoglobin-based blood substitutes is discussed.
Key Words Raffinose; porcine hemoglobin;
blood substitutes
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