A　novel　electrochemical　microbial　biosensor　for　the　rapid　monitoring　of　p-nitrophenyl-substituted　organophosphates　(OPs)　compounds　based　on　glass　carbon　electrode　(GCE)　modified　with　both　ordered　mesopore　carbons　(OMCs)　and　cell　surface-expressed　organophosphorus　hydrolase　(OPH)　(OPH-bacteria/　OMCs/GCE)　was　described　in　this　paper.　The　genetically　engineered　Escherichia　coli　strain　surface　displayed　mutant　OPH　(55)　with　improved　enzyme　activity　and　favorable　stability　was　constructed　using　a　newly　identified　N-terminal　of　ice　nucleation　protein　as　an　anchoring　motif,　which　can　be　used　directly　without　further　time-consuming　enzyme-extraction　and　purification,　thereafter　greatly　improved　the　stability　of　the　enzyme.　Compared　to　OPH-bacteria　modified　GCE　(OPH-bacteria/GCE),　the　OPH-bacteria/OMCs/GCE　not　only　significantly　enhanced　the　current　response　but　also　reduced　the　oxidation　overpotential　towards　oxidizable　p-nitrophenol　(p-NP),　which　was　the　hydrolysate　of　p-nitrophenyl-substituted　OPs.　Under　the　optimized　experimental　conditions,　at　+0.84　V　(vs.　SCE),　the　current-time　curve　was　performed　with　varying　OPs　concentration.　The　current　response　was　linear　with　paraoxon　concentration　within　0.05-25　mu　M.　Similarly,　linear　range　of　0.05-25　mu　M　was　found　for　parathion,　and　0.08-30　mu　M　for　methyl　parathion.　The　low　limits　of　detection　were　evaluated　to　be　9.0　nM　for　paraoxon,　10　nM　for　parathion　and　15　nM　for　methyl　parathion　(S/N=3).　Thus,　a　highly　specific,　sensitive　and　rapid　microbial　biosensor　was　established,　which　holds　great　promise　for　on-site　detection　of　trace　p-nitrophenyl-substituted　OPs.　(C)　2014　Elsevier　B.V.　All　rights　reserved.