Extraction of Genomic DNA from bacteria

\documentclass[a4paper,12pt]{article}
%\documentclass[a4paper,12pt]{scrartcl}
\usepackage[utf8]{inputenc}
\usepackage[T1]{fontenc}
\usepackage{textcomp}
\usepackage{mhchem}
\usepackage[mediumspace,mediumqspace,Grey,squaren]{SIunits}
\usepackage{color}
\usepackage{fixltx2e}
\usepackage[top=1.5cm, bottom=1.5cm,left=1.5cm, right=1.5cm]{geometry}
% \setromanfont[Mapping=tex-text]{Linux Libertine O}
% \setsansfont[Mapping=tex-text]{DejaVu Sans}
% \setmonofont[Mapping=tex-text]{DejaVu Sans Mono}

%\title{Extraction of Genomic DNA from bacteria}
\author{}
\date{}

\begin{document}
\maketitle

\begin{enumerate}

\item Grow 100 ml of a bacterial culture overnight in the appropriate medium.
\item On the  next morning, centrifuge to precipitate the cells.
\item Resuspend the pellet in 5 ml solution A.
\item Incubate overnight at –20 C or 15 min at –70 C.
\item To the frozen bacteria add 0.5 ml of solution B.
\item  Thaw the bacteria by gently agitating the tube at R.T.; move to ice for 45 min.
\item  Add 1 ml sol. C. Incubate for 60 min at 50 C with gentle agitation.
\item  Move to 37 C overnight.
\item  On the next morning, add 6 ml phenol (pH 7.5-8), mix by inversion and centrifuge 15 min at 7000 rpm.
\item   Transfer the aqueous phase to a new tube, add 1 volume of phenol, centrifuge as above, extract the aqueous phase with chloroform.
\item   Add 1/10 vol of 3 M sodium acetate (pH 5) and 2 volumes of 100\% EtOH.
\item  With the help of a thin glass stick or a “yellow” tip, roll up the DNA and transfer it to an eppendorf tube.
\item   Add 500 µl of 70% EtOH and centrifuge 2 min at max. speed.
\item  Wash again with 70% EtOH.
\item  Briefly air-dry the pellet and resuspend in 0.5 ml sterile mili-Q water or TE.

Solution A- 50 mM EDTA + 50 mM Tris pH 8
Solution B- 10 mg/ml lysozyme in 0.25 M Tris pH 8
Solution C- 1 mg/ml proteinase K, 0.5% SDS, 0.4 mM EDTA, 50 mM Tris pH 7.5

\end{enumerate}

\end{document}