Nos.: For Out-patient Concerns â MMC Trunk line: (0632)8888-999 local 7330 / Direct line (0632)893-6064 / Grandstream: local (0632)908-6900 local 1375. For In-patient Concerns â MMC Trunkline (0632)8888-999 local 7331. Hours: 7AM â 7PM Mondays to Fridays, Saturday 7AM â 4PM. (CLOSED DURING SUNDAYS AND HOLIDAYS).
The Heme Group. In hemoglobin, each subunit contains a heme group, which is displayed using the ball-and-stick representation in Figure 2. Each heme group contains an iron atom that is able to bind to one oxygen (O 2) molecule. Therefore, each hemoglobin protein can bind four oxygen molecules. One of the most important classes of chelating agents in nature are the porphyrins.
Myoglobin can bind a single oxygen molecule between the distal histidine and the heme iron atom. Hydrogen bonding of the distal histidine and the oxygen crowds the area enough to cause the oxygen to bind at an angle with respect to the plane of the heme group (Pratt and Cornely 2004).