Converting micrograms to moles for IgG
Student
convert mass to moles for small molecules, I have never done it for large
proteins. For an IgG1 molecule, I know the size is approximately 150kDa.
Does this mean that 1 mole = 150,000grams? (It would be rather tedious to
add up all the molecular weights of the amino acids to get the molar mass!)
Thanks, and excuse my ignorance!
Mike Clark
150,000 Mr is a good working round figure approximation for an IgG
molecule.
As a useful rule of thumb I generally estimate as follows
a single Ig domain = 12,500 Mr
there are two of these in a light chain = 25,000 Mr
and four in a heavy chain = 50,000 Mr
An IgG has two heavy and two light = (2x25,000)+(2x50,000) = 150,000
Mike <URL:http://www.path.cam.ac.uk/~mrc7/>
--
o/ \\ // || ,_ o M.R. Clark, PhD. Division of Immunology
<\__,\\ // __o || / /\, Cambridge University, Dept. Pathology
"> || _`\<,_ // \\ \> | Tennis Court Rd., Cambridge CB2 1QP
` || (_)/ (_) // \\ \_ Tel.+44 1223 333705 Fax.+44 1223 333875
clarosa
Rich Miller
Rich Miller
engelbert...@my-deja.com
"Student" <muci...@iname.com> wrote:
> (It would be rather tedious to
> add up all the molecular weights of the amino acids to get the molar
mass!)
Once a protein is sequenced, there are computer programs that handle the
maths for you. Antheprot and similar utilities will calculate how many
times each amino acid occurs in the protein, its molecular weight, pI,
molar absorbance coeficient at 280 nm, hydropathy profile, prediction of
antigenic segments and secondary structure and a lot more. Check the
biology section at SIMTEL or HENSA, if you are interested in such
utilities, many of which are freeware. Some of them are also run on the
net, Pedro's Molecular Biology Homepage
http://www.biophys.uni-duesseldorf.de/bionet/research_tools.html will
point you to these resources.
Sent via Deja.com http://www.deja.com/
Before you buy.
Student
I am confused. So can someone confirm this is right:
1 mole of a protein means there is 6.02x10E23 molecules of that protein. and
for an IgG, 150,000grams of the antibody will contain 6.02E23 IgG molecule
which is 1 mole of IgG?
> No, 1 mole is about 150,000 grams.
>
> Rich Miller
>
> clarosa wrote:
>
> > yes 1 mole is about 150 kDA..given that the size is an estimate.
> >
> > Student wrote:
> >
> > > This may sound a very silly question to many of you. Whilst I know how
to
> > > convert mass to moles for small molecules, I have never done it for
large
> > > proteins. For an IgG1 molecule, I know the size is approximately
150kDa.
> > > Does this mean that 1 mole = 150,000grams? (It would be rather tedious
to
> > > add up all the molecular weights of the amino acids to get the molar
mass!)
> > >
Mike Clark
Unfortunately many proteins have post-translational modifications so that a
precise measurement of the Mr predicted from the DNA sequence will not be
correct. Immunoglobulin has N-linked and O-linked glycosylation depending
upon the class and subclass.
Francis Durst
moon, whilst it will weight much less than 150 kg on the moon
Francis
In article
<8ur6ug$4nb$1...@oyez.ccc.nottingham.ac.uk> "Student" <muci...@iname.com>
writes:>From: "Student" <muci...@iname.com>>Subject: Re: Converting
micrograms to moles for IgG>Date: Tue, 14 Nov 2000 11:16:41 -0000
>I thought 150kDa means approximately 150,000grams?
>I am confused. So can someone confirm this is right:
>1 mole of a protein means there is 6.02x10E23 molecules of that protein. and
>for an IgG, 150,000grams of the antibody will contain 6.02E23 IgG molecule
>which is 1 mole of IgG?
>> No, 1 mole is about 150,000 grams.
>>
>> Rich Miller
>>
>> clarosa wrote:
>>
>> > yes 1 mole is about 150 kDA..given that the size is an estimate.
>> >
>> > Student wrote:
>> >
>> > > This may sound a very silly question to many of you. Whilst I know how
>to
>> > > convert mass to moles for small molecules, I have never done it for
>large
>> > > proteins. For an IgG1 molecule, I know the size is approximately
>150kDa.
>> > > Does this mean that 1 mole = 150,000grams? (It would be rather tedious
>to
>> > > add up all the molecular weights of the amino acids to get the molar
>mass!)
>> > >
Michael L. Sullivan
Both the dalton and the gram are units of mass. The dalton is defined as
1/12 the mass of a C-12 atom. A mole of molecules will have the gram mass
of it's molecular weight in daltons. So, one IgG molecule has a mass of
about 150 kdaltons, and a mole of IgG molecules has a mass of about 150 kg.
Mike
>The dalton is a mass unit : your IgG will be 150 kDA on earth and on the
>moon, whilst it will weight much less than 150 kg on the moon
>Francis
>
>In article
><8ur6ug$4nb$1...@oyez.ccc.nottingham.ac.uk> "Student" <muci...@iname.com>
>writes:>From: "Student" <muci...@iname.com>>Subject: Re: Converting
>micrograms to moles for IgG>Date: Tue, 14 Nov 2000 11:16:41 -0000
>
>>I thought 150kDa means approximately 150,000grams?
>
>>I am confused. So can someone confirm this is right:
>
---
Cornelius Krasel
Yes.
> for an IgG, 150,000grams of the antibody will contain 6.02E23 IgG molecule
> which is 1 mole of IgG?
Exactly.
--Cornelius.
--
/* Cornelius Krasel, U Wuerzburg, Dept. of Pharmacology, Versbacher Str. 9 */
/* D-97078 Wuerzburg, Germany email: kra...@wpxx02.toxi.uni-wuerzburg.de */
/* "Science is the game we play with God to find out what His rules are." */
Cornelius Krasel
> The dalton is a mass unit : your IgG will be 150 kDA on earth and on the
> moon, whilst it will weight much less than 150 kg on the moon
The kg is also a mass unit. 1 kg of whatever material on earth is also
1 kg on the moon.
Mike Clark
<URL:mailto:mlsu...@facstaff.wisc.edu> wrote:
> Freshman Chemistry:
>
> Both the dalton and the gram are units of mass. The dalton is defined as
> 1/12 the mass of a C-12 atom. A mole of molecules will have the gram mass
> of it's molecular weight in daltons. So, one IgG molecule has a mass of
> about 150 kdaltons, and a mole of IgG molecules has a mass of about 150 kg.
>
> Mike
>
You can of course use "relative molecular mass" or Mr (suffix r) and being
a ratio it is unitless and hence always the same.
clarosa
Student wrote:
> I thought 150kDa means approximately 150,000grams?
>
> I am confused. So can someone confirm this is right:
>
> 1 mole of a protein means there is 6.02x10E23 molecules of that protein. and
> for an IgG, 150,000grams of the antibody will contain 6.02E23 IgG molecule
> which is 1 mole of IgG?
>
Gauthier , Eric
---
hamza...@gmail.com
See more at:-> http://www.oslohudlegesenter.no/f%C3%B8flekker-bid-32.html
http://www.oslohudlegesenter.no/
wachsm...@gmail.com
> This may sound a very silly question to many of you. Whilst I know how to
> convert mass to moles for small molecules, I have never done it for large
> proteins. For an IgG1 molecule, I know the size is approximately 150kDa.
> Does this mean that 1 mole = 150,000grams? (It would be rather tedious to
> add up all the molecular weights of the amino acids to get the molar mass!)
>
> Thanks, and excuse my ignorance!
54 gram for salt is one mole I think. 150,000 gram is one mole of antibody G. Believe me, we only need to care about the order of magnitude for this. that would be 150,000 mg per milliliter for one mole and 20 ug/ml for what you get at the most for an antidrug vaccine. 2 x 10-1mg/ml/1.5 x 10 105 is something 10 -6 molar. Not too bad, actually. It totally sucked for drugs taken many times at many moles (cocaine, crystal, nicotine). IT MIGHT not be TOO bad for ONE dose of the very potent fentanyl. but... it lowers the brain concentration by 60%. It increases the half life of the fentanyl by 100%. If they take ONE MORE DOSE... yeah, ok... reference me if you publish this month. I plan to work on it next month.
so, yeah, yer kung fu is good, my son. and don't expect to be immune if you get the vaccine for fentanyl.