[ccp4bb] Crystals with Organic solvents

Dear All I was working on a Human protein and expression and solubility is good in E.coli and purification is One step (His-Tag), and i need to cleave the Histag before screens, if not the protein will precipitated and Aggregated, but after trying for 1.2 years i have crystals

[ccp4bb] crystal Packing

thinking one domain might be flexible and other is stable is there anyway to increase the crystal packing Any suggestions are welcome. Eswar Reddy