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Specialty Chemistry Forums => Biochemistry and Chemical Biology Forum => Topic started by: adianadiadi on December 04, 2017, 02:23:54 PM

Title: Substitution of Magnesium in chlorophyll
Post by: adianadiadi on December 04, 2017, 02:23:54 PM
We know that there is Mg2+ ion in chlorophyll. What will happen if it is replaced by Zn2+ ion or Ca2+ ion. Any thing special about Mg...? Nature has chosen this ion. Is it just size or also the stability...?
Title: Re: Substitution of Magnesium in chlorophyll
Post by: Babcock_Hall on December 04, 2017, 02:39:13 PM
It is a forum rule that you must provide your thoughts before we can help you.
Title: Re: Substitution of Magnesium in chlorophyll
Post by: Arkcon on December 04, 2017, 04:11:44 PM
That chlorophyll center is called a tetrapyrrole ring.  You might want to look up other molecules that use that ring, and see some other metals in the center.  Then, you can try to infer what the metal ion center means.  Its a good way to learn.
Title: Re: Substitution of Magnesium in chlorophyll
Post by: adianadiadi on December 07, 2017, 02:13:32 PM
It is a forum rule that you must provide your thoughts before we can help you.

I already stated that - may be size or stability are the factors. My understanding/knowledge is not going more than this. If you have anything in your mind, I would like to know..
Title: Re: Substitution of Magnesium in chlorophyll
Post by: Babcock_Hall on December 07, 2017, 03:44:57 PM
Metal ions differ in their ability to participate in redox chemistry, in the number of ligands that they prefer to coordinate, and in their coordination geometry (there are additional properties that one might consider).  One of these three you can ignore for the metal ions that you mentioned.  Which one?
Title: Re: Substitution of Magnesium in chlorophyll
Post by: Corribus on December 08, 2017, 09:30:26 AM
They also differ in the spectroscopic/optical properties when bound to a porphyrin (or related) center, which as you might imagine would be important for a photoactive redox center.