Thursday, 11 April 2013


  • Metals play roles in approximately one-third of the known enzymes. Metals may be a co-factor or they may be incorporated into the molecule, and these are known as metalloenzymes. 
  • Amino Acids in peptide linkage posses groups that can form coordinate-covalent bonds with the metal atom. The free amino and carboxy group bind to the metal affecting the enzymes structure resulting in its active conformation.
  • Metals main function is to serve in electron transfer. Many enzymes can serve as electrophiles and some can serve as nucleophilic groups. This versatility explains metals frequent occurrence in enzymes. Some metalloenzymes include hemoglobins, cytochromes, phosphotransferases, alcohol dehydrogenase, arginase, ferredoxin, and cytochrome oxidase.
  • Carboxypeptidase A is a zinc metalloenzyme that breaks peptide linkages in the digestion of proteins. The zinc ion that the enzyme contains in its active site plays a key role in that function.
Structure of Fe(III)-peroxo complex, [Fe(TMC)(OO)]+. Hydrogen atoms are omitted for clarity. Key bond distances are shown on the structure. Image Credit:


No comments:

Post a Comment

Thank you for writing to "Chemical Science"

Message from Bhagavath Geetha
  • Do not get over excited over happiness and do not get over depressed over sorrow.
  • Do not get over bonded with anyone and anybody because it can lead to problems and sorrow.
  • Never think that my duty is the topmost or lowermost. Every duty is respectful. The responsibility undertaken or given as per the position is the noblest duty.
  • Elevate yourselves, family, society and nation and never denigrate yourselves, family, society and nation.
  • We are our own closest relatives and if not properly utilised we will become our closest enemies.
  • There are possibilities of success and failure in any endeavour. One cannot assure success always.
  • Death is inevitable for everyone in this world. In any endeavour at the maximum an individual may die.
  • People may say good and also they may say bad. Approach them with stabilised mind.
  • Take anything after scientifically, logically and rationally analysing them.
  • Perform your duty, responsibility and accept the privileges eligible for you.
  • First change ourselves and then try to change others.
  • We are all instruments /tools in the hands of the nature for performing the duty. So do not think that I am doing the duty. Think that I am an instrument to do the duty.
  • Results of action may not be sweet always. Accept what ever may be the result.
  • Follow the path of great scholars who guided the world. Listen their messages.
  • Results and rewards will come and go but stick to your duty with devotion, dedication and sincerity.