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I have been reading about Maltose Binding Proteins. Mutant forms of the molecule seem to be named MalE_ where the _ represents a number, for example MalE36 or MalE50.

Please can someone explain the naming convention for this? i.e. what does the 'E' stand for? Does the number refer to the amino acid that has changed?

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I know that usually both amino acids and the position are named, for example BRAF V600E means an exchange of valine against glumatic acid at position 600 of BRAF. – Chris Jun 10 '14 at 21:30

MalE is the gene that encodes the maltose-binding protein in E. coli. If you look at the genotype of any E. coli strain you will see similar nomenclature. Everything in the answer from @Bez is correct, but in this case the E has nothing to do with glutamate.

The numbers are probably just arbitrary numbers that were assigned to the individual mutations, but you would need to provide a link to a source before this could be confirmed.

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What your example is referring to is the change in the glutamic acid (E) amino acid (AA) residue, which is in position 36. This is denoted so that people/scientist would know what has been changed and usually there should be another letter after that number such as Y, which is tyrosine, to denote what it has been changed to, if it is a substitution. Then there is the delta (∆) symbol to denote deletion, and usually a number range e.g. 36-50 or just a number e.g. 70 appears after it to denote if a protein has been truncated in a certain AA range or if the entire protein from that AA is truncated, respectively. Sometimes (quite often now a days) the delta symbol is followed a protein domain name such as SH3 or RA to denote that a protein domain has been deleted and people use all sorts of naming variations for a protein that has been altered from its native sequence, which can be confusing!!

These are just some conventions, which isn't documented very well and you just figure them out when reading a few papers but I would welcome any edits for a good source for protein change annotations.


Since as pointed by Alan Boyd response, MalE is an E. coli gene encoding Maltose Binding Proteins, then my answer will not apply for any protein AA changes as correctly pointed out and elaborated on in Alan Boyd response.

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