chain starting number once the chain is already created

dear all,

I am currently doing an assignment in the v3.0.4 and I forgot to change the starting residue number. Is it possible to change it after the assignment process has started?


Yes, the synthax is:

chain.renumberResidues(offset, start, stop)
nmrChain.renumberNmrResidues(offSet, start, stop)

see a previous thread:

Just to clarify - if you have an already residue-specifically assigned chain you need to renumber both the chain and the nmrChain to fix the issue.

First archive your project in case anything goes wrong!

Check what the chains (what you told the program about your molecule(s) when you input the sequence) that you have in your project are by opening the Python console (space, space) and typing:


you’ll see square bracketed list with comma separated items in it. In most cases you will have only one chain (something like MC:A) which you can access as project.chain[0], otherwise count along the list starting at 0 to find the chain you want to renumber.

To find the corresponding nmrChain (which is probably not project.nmrChains[0] as that’s usually the default NC:@- one and there may be others created by linking nmrResidues together) type:


This should show something like NC:A

Now you can do the renumbering:

myChain = project.chains[0]
myNmrChain = myChain.nmrChain
myChain.renumberResidues(offset, start, stop)
myNmrChain.renumberNmrResidues(offSet, start, stop)

Some modules (e.g. Backbone Assignment) may need to be closed and reopened to catch up with the changes.