I hope you are well. I am a student at Swarthmore College and am currently trying to use Chimera X to covalently attach glycans to asparagine residues. I was able to get 3 out of 5 of the glycans attached by selecting both atoms > structure editing > build structure > adjust bonds > add reasonable bonds. I did the same process for the other 2 glycans and no bond was made. The log says bond sel, 0 bonds. The glycans are combined with the protein using the combine command. 

I believed it may be an issue with an unreasonable binding distance but when I moved the glycan closer, the bond still didn't work. What else should I try? Also, do you know why it is working for some glycans but not others?

Best,

Ellie Streeper