Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Presence of pKa Perturbations Among Homeodomain Residues Facilitates DNA
  Binding   Homeodomain containing proteins are a broad class of DNA binding proteins
that are believed to primarily function as transcription factors.
Electrostatics interactions have been demonstrated to be critical for the
binding of the homeodomain to DNA. An examination of the electrostatic state of
homeodomain residues involved in DNA phosphate binding has demonstrated the
conserved presence of upward shifted pKa values among the basic residue of
lysine and arginine. It is believed that these pKa perturbations work to
facilitate binding to DNA since they ensure that the basic residues always
retain a positive charge.

9
The categories of this paper are: nlin
5
The categories of this paper are: gr-qc
36
The categories of this paper are: cmp-lg
37
The categories of this paper are: supr-con
32
The categories of this paper are: atom-ph
12
The categories of this paper are: nucl-th
27
The categories of this paper are: comp-gas
2
The categories of this paper are: math
28
The categories of this paper are: alg-geom
33
The categories of this paper are: plasm-ph
21
The categories of this paper are: adap-org
14
The categories of this paper are: math-ph
26
The categories of this paper are: bayes-an
20
The categories of this paper are: acc-phys
13
The categories of this paper are: quant-ph
35
The categories of this paper are: mtrl-th