The amilose resin as first purification step can already give protein 70-80% pure. I usually run the elution through a MonoQ column as a polishing step. The MBP on its own elutes around 200mM NaCl.

You can skip the amilose in case you have a His tag on your MBP or on your Cterm, anyway I do not think you can totally avoid an affinity chromatography step. I might be wrong though.

MBP is easily release from amylose resin by the contaminated sugar. If you carefully avoid this issue, the affinity chromatography using amylose resin would be very useful.

We lyse the cells with 20 mM Tris pH 8, 300 mM NaCl, 10% glycerol and purify with an amylose column eluting with 10 mM maltose and then follow that with a size exclusion column equilibrated in lysis buffer. You can probably omit the glycerol as MBP is extremely soluble. Purity is greater than 90%.

Is your MBP tag cleavable?  If so, I like double-SEC as an alternative:  First, purify the large fusion protein.  It will of course co-elute with a whole bunch of E. coli proteins having similar Mw.  Then, you cleave the tag.  Much smaller TEV gets released, and you can pick it up very pure with a second step of SEC. 

Since you have a TEV tag after MBP, just apply the crude protein on to amylose column so that all the mbp tagged protein binds to the column. NOw wash the column throughly to remove off any unbound protein. Once you r sure there is not protein eluting out close the column, add some buffer and add some TEV protease and cleave off the tag by incubating for few hours. Now collect the flow through. This should purify your protein of interest without the tag. If there remains some impurities do gel filtration to get rid of this. Hope this works. All the best

Thank you all. can you tell me how much TEV protease I should add to the tagged protein?

It usually depends on the individual protein properties and the optimal ratio should be set empirically. See here: http://www.protean.cz/en/recombinant-protein/28/tev-protease