ISSN:
1573-4919
Keywords:
anomeric preference
;
glucose anomer
;
glucose utilization
;
rat erythrocytes
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
,
Chemistry and Pharmacology
,
Medicine
Notes:
Abstract The β-anomer of glucose relative to the α-anomer was more rapidly metabolized into lactate by rat erythrocytes at 37° C (β/α ratio = ca. 1.3): the amounts of α- and β-D-glucose metabolized into lactate during 3 min were 0.21 and 0.27 μmol/gHb, respectively. Also, the transport of β-D-glucose into erythrocytes was more rapid than that of α-D-glucose: the amounts of α- and β-D-glucose transported into erythrocytes during 3 min were approximately 3.5 and 5.0 μmol/gHb, respectively. Glucose phosphorylation by rat erythrocyte hexokinase (i.e., a possible rate-limiting step in glycolysis) occurred at higher velocities with the β-anomer than with the a-anomer (β/α ratio = 1.28). The Km value of hexokinase for either anomer of glucose was 53 μM. The glucose concentrations in erythrocytes incubated with α- and β-D-glucose reached about 1 mM in 1 min, indicating that hexokinase is almost completely saturated with glucose within less than 1 min. The results suggest that glucose phosphorylation and glucose transport are major and minor determinants, respectively, for the anomeric preference of glucose utilization in rat erythrocytes.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00229639
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