Carbon monoxide, binding hemoglobin

Carboxyhemoglobin Hemoglobin that has bonnd CO is called carboxy-hemoglobin. Carbon monoxide binds to hemoglobin with 200 times the affinity of O. ... 

Carbon monoxide binds to cytochrome a/Oj but less tightly than cyanide. It also binds to hemoglobin, displacing oxygen. Symptoms include headache, nausea, tachycardia, and tachypnea. Lips and cheeks turn a cherry-red color. Respiratory depression and coma result in death if not treated by giving oxygen. Sources of carbon monoxide include ... 

Carbon monoxide Binds to hemoglobin, reducing oxygen delivery to tissues Headache, dizziness, nausea, vomiting, seizures, coma... 

The mechanism underlying carbon monoxide poisoning is well understood at the biochemical level. Carbon monoxide binds to the iron atom in hemoglobin at the same binding site as oxygen, but it binds more avidly, indeed about 240 times more strongly. The product is carboxyhemoglobin, which may contain one or more carbon monoxide molecules. 

Figure 7.66 The heme moiety of the hemoglobin molecule showing the binding of the oxygen molecule to the iron atom. As shown in the diagram, carbon monoxide binds at the same site. Abbreviation His, side chain of the amino acid histidine. Source From Ref. 18.

Though not a global threat, carbon monoxide, CO, can be a serious health threat. This is because carbon monoxide binds very strongly to hemoglobin and prevents blood from transporting oxygen to body tissues (see Chapter 11). 

Huang Y, Ackers GK. Transformation of cooperative free energies between ligation systems of hemoglobin resolution of the carbon monoxide binding intermediates. Biochemistry 1996 35 704-718. 

Carbon monoxide binds very strongly to hemoglobin in red blood cells, resulting in the production of carboxyhemoglobin (COHb) this can actually be used as a marker for exposure to carbon monoxide. The presence of COHb impairs the normal transport of oxygen within the blood and can result in adverse effects on tissues, such as those in the cardiovascular and nervous systems, which have high oxygen needs. 

Carbon monoxide binds 220 times more avidly to hemoglobin than O. ... 

Carbon monoxide binds tightly to the heme groups of hemoglobin and myoglobin. How does this affinity reflect the toxicity of carbon monoxide ... 

The chent should receive high levels of oxygen. Carbon monoxide binds to the hemoglobin molecule with a greater affinity than oxygen. It is imperative to get oxygen to the client as qnickly as possible. 

There are many ways to seriously disrupt our biological machine. Carbon monoxide binds to hemoglobin and prevents oxygen from getting to our cells. Cyanide shuts down the production of ATP in mitochondria. Hemlock is a weed that contains a mixture of at least eight rather toxic molecules that target the nervous system. Thallium ions (TH) are particularly toxic because they are highly water soluble and once in the body they bind to ion channels and disrupt other processes that normally function with potassium ions (K" "). 

Some substances, such as CO, form strong bonds to the iron of heme, strong enough to displace O2 from it. Carbon monoxide binds 30-50 times more effectively than oxygen to myoglobin and hundreds of times better than oxygen to hemoglobin. 

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