title: Scanning tunnelling microscopy observations of biomolecules on layered materials.
abstract: Scanning tunnelling microscopy (STM) has been performed on the reverse transcriptases of the human immunodeficiency virus (HIV-1) and the moloney murine leukaemia virus (MuLV). The biological molecules are adsorbed on n-type semiconducting MoTe2. The p66 (66 kD) subunit of the RT of HIV-1 is imaged by STM. Both STM and processed transmission electron microscopy (TEM) data show a spherical and horseshoe-like shape of external diameter ca. 65 A, depending on the angle of observation. The STM results show a larger diameter which is related to the curvature radius of the tip of the probing needle. The RTs of HIV-1 and MuLV exhibit a circular hole of ca. 20 A diameter in accordance with structure predictions and functioning considerations. The surface-molecule interaction is discussed in terms of the electronic properties of the semiconductor surface including the influence of small defect sites at the layered crystal surface.
authors.affiliation: Hahn-Meitner-Institut Berlin, Bereich Photochemische Energieumwandlung, Germany.
authors.forename: H
authors.initials: H
authors.lastname: Jungblut
authors.forename: S A
authors.initials: SA
authors.lastname: Campbell
authors.forename: M
authors.initials: M
authors.lastname: Giersig
authors.forename: D J
authors.initials: DJ
authors.lastname: Müller
authors.forename: H J
authors.initials: HJ
authors.lastname: Lewerenz
mesh_terms: D003956:Dialysis; D054303:HIV Reverse Transcriptase; D015497:HIV-1 / Q000201:enzymology; D016252:Microscopy, Scanning Tunneling; D008979:Moloney murine leukemia virus / Q000201:enzymology; D009502:Neutrons; D012194:RNA-Directed DNA Polymerase / Q000032:analysis*; D012542:Scattering, Radiation; D013056:Spectrophotometry, Ultraviolet
chemical_list: D054303:HIV Reverse Transcriptase; D012194:RNA-Directed DNA Polymerase