Last couple to sharpen axes with me - a catalyst for change (6)
I believe the answer is:
enzyme
'me a catalyst for change' is the definition.
I can't tell whether this defines the answer.
'last couple to sharpen axes with' is the wordplay.
'last' says to take the final letters.
'axes with' becomes 'zyme' (I can't justify this - if you can you should give a lot more credence to this answer).
The final letters of 'couple sharpen' are 'en'.
'en'+'zyme'='ENZYME'
Can you help me to learn more?
(Other definitions for enzyme that I've seen before include "Protein product of living cells" , "Catalytic protein substance" , "Protein substance acting as a catalyst" , "Catalyst made of protein" , "E.g. pepsin" .)