Projecting On Attribute Identified By String In SELECT?

I'm trying to map a database (with a stupid schema) into an ontology. That's why I need to do such a stupid query (as you will see). Here is the structure of the table:

CodonUs {
ID STRING PRIMARY KEY,
GCT FLOAT,
GCC FLOAT,
GTC FLOAT,
and so on for all possible triplets

What I would like to do is to have a query that joins the organisme table on the ID and extract the name of the triplet (thus, the name of the column) and the exact value:

SELECT ID, 'GCT' AS Codon, Codon

FROM organisme JOIN codonUs ON Abbrev = ID

The result set should be something like:

ID of the organisme | Name of the triplet | Value of the triplet