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Old 01-17-2014
drharmonis's Avatar
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Default confusion on high Km and low affinity

Hi guys, would really appreciate if you could help me to cleae this confusion. In kaplan biochem 2013, pg174. GLUT 2 and glucokinase have high Km values for glucose. Glucose is transported n phosphorylated via first order kinetics. But in a near-complete deficiency glucokinase activity, baby is exposed to permanent type 1 DM.
Does that mean in that in the abscence of glucokinase, excess glucose frm intestine is not taken up by liver, thst it goes to circulation and neonatal DM 1 occured?

My second question is, the relationship of Km and affinity. I can understand the Km n affinity, but can correlate with hyperinsulinaemia. I can understand the rebounced effect of hyperglycaemia, but cant correlate the Km and affinity..

Would appreciate soo much,,
Thanxxxx
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Old 01-17-2014
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Quote:
Originally Posted by drharmonis View Post
Hi guys, would really appreciate if you could help me to cleae this confusion. In kaplan biochem 2013, pg174. GLUT 2 and glucokinase have high Km values for glucose. Glucose is transported n phosphorylated via first order kinetics. But in a near-complete deficiency glucokinase activity, baby is exposed to permanent type 1 DM.
Does that mean in that in the abscence of glucokinase, excess glucose frm intestine is not taken up by liver, thst it goes to circulation and neonatal DM 1 occured?

My second question is, the relationship of Km and affinity. I can understand the Km n affinity, but can correlate with hyperinsulinaemia. I can understand the rebounced effect of hyperglycaemia, but cant correlate the Km and affinity..

Would appreciate soo much,,
Thanxxxx
1st question: yes with no glucokinase, glucose will not be trapped by any cell including the liver!

2nd:
i dont know! hope someone will clear this out.
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drharmonis (01-17-2014)
  #3  
Old 01-17-2014
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Cool

Thanx!!!
Would appreciate soo much if someone could explain! Cheers!
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