Recently there has been a great interest in graphene nanostructures owing mainly to its unique electrical properties where conductivity exhibits low Johnston noise, low charge scattering and ballistic transport. Study of graphene's chemical modification, its structure and its integration with other biological/chemical systems will open avenues to further broaden its impact to include areas like biophysics, solar cells, chemical circuitry etc. We are studying electronic and structural properties of graphene-biohybrids and chemically modified graphene (CMG) nanostructures. Specifically, we have built graphene-bacteria ensembles, DNA-tethered graphene-structures, polyelectrolyte adsorbed CMG nanostructures. We are interested in the effect of chemical modification of graphene on its structure, such as formation of wrinkles on surface and creation of folds etc. Further we are also investigating the effect of inherent wrinkles and folds on the modification of CMGs. The electrical properties of all the CMG-sheets are distinctly different from pristine graphene. We are studying the electrical properties of (a) CMG's hybrids with single bacterial cell attachment, (b) CMG with DNA (single strand and double strand) tethered and hybridized on surface and (c) CMG with polyelectrolyte-layer assembled on surface. These hybrids function as: (a) single bacterium devices, (b) DNA hybridization sensor and (c) charge polarity sensitive chemical-detector, respectively. We are also characterizing the system for (1) stress application on single bacterial cell on CMG, (2) single molecular attachment on CMG and (3) selective ‘wrapping' of CMG-sheets on bacterium.