Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Interactions of aqueous amino acids and proteins with the (110) surface
  of ZnS in molecular dynamics simulations   The growing usage of nanoparticles of zinc sulfide as quantum dots and
biosensors calls for a theoretical assessment of interactions of ZnS with
biomolecules. We employ the molecular-dynamics-based umbrella sampling method
to determine potentials of mean force for 20 single amino acids near the ZnS
(110) surface in aqueous solutions. We find that five amino acids do not bind
at all and the binding energy of the remaining amino acids does not exceed 4.3
kJ/mol. Such energies are comparable to those found for ZnO (and to hydrogen
bonds in proteins) but the nature of the specificity is different. Cysteine can
bind with ZnS in a covalent way, e.g. by forming the disulfide bond with S in
the solid. If this effect is included within a model incorporating the Morse
potential, then the potential well becomes much deeper - the binding energy is
close to 98 kJ/mol. We then consider tryptophan cage, a protein of 20 residues,
and characterize its events of adsorption to ZnS. We demonstrate the relevance
of interactions between the amino acids in the selection of optimal adsorbed
conformations and recognize the key role of cysteine in generation of lasting
adsorption. We show that ZnS is more hydrophobic than ZnO and that the density
profile of water is quite different than that forming near ZnO - it has only a
minor articulation into layers. Furthermore, the first layer of water is
disordered and mobile.

20
The categories of this paper are: acc-phys
31
The categories of this paper are: ao-sci
8
The categories of this paper are: hep-ex
26
The categories of this paper are: bayes-an
21
The categories of this paper are: adap-org
29
The categories of this paper are: funct-an
16
The categories of this paper are: stat
28
The categories of this paper are: alg-geom
23
The categories of this paper are: solv-int
6
The categories of this paper are: astro-ph
3
The categories of this paper are: physics
12
The categories of this paper are: nucl-th
30
The categories of this paper are: q-alg
5
The categories of this paper are: gr-qc
22
The categories of this paper are: chao-dyn
18
The categories of this paper are: econ