Based　on　the　crystal　structure　of　the　vitamin　B-12　transporter　protein　of　Escherichia　coli　(BtuCD)　a　system　consisting　of　the　BtuCD　transmembrane　domain　(BtuC)　and　the　palmitoyloleoyl　phosphatidylcholine　(POPC)　lipid　bilayer　was　constructed　in　silica,　and　a　more-than-57-nanosecond　molecular　dynamics　(MD)　simulation　was　performed　on　it　to　reveal　the　intrinsic　functional　motions　of　BtuC.　The　results　showed　that　a　stable　protein-lipid　bilayer　was　obtained　and　the　POPC　lipid　bilayer　was　able　to　adjust　its　thickness　to　match　the　embedded　BtuC　which　underwent　relatively　complicated　motions.　These　results　may　help　to　understand　the　mechanism　of　transmembrane　substrate　transport　at　the　atomic　level.