TY - JOUR
T1 - Interactions between dissolved natural organic matter and adsorbed DNA and their effect on natural transformation of Azotobacter vinelandii
AU - Lu, Nanxi
AU - Mylon, Steven E.
AU - Kong, Rong
AU - Bhargava, Rohit
AU - Zilles, Julie L.
AU - Nguyen, Thanh H.
N1 - Funding Information:
We gratefully acknowledge Ms. Lou Ann Miller and Dr. Changhui Lei from Material Research Laboratory at University of Illinois for their advice on TEM and Dr. Dennis Dean for supplying A. vinelandii strains and protocols. This research was supported by the USDA (grant 2008-35102-19143 ) and National Science Foundation agreement number EAR-1114385 , CTS-0120978 and CHE-0957849 .
PY - 2012/6/1
Y1 - 2012/6/1
N2 - To better understand gene transfer in the soil environment, the interactions between dissolved natural organic matter (NOM) and chromosomal or plasmid DNA adsorbed to silica surfaces were investigated. The rates of NOM adsorption onto silica surfaces coated with DNA were measured by quartz crystal microbalance (QCM) and showed a positive correlation with carboxylate group density for both soil and aquatic NOM in solutions containing either 1mM Ca 2+ or Mg 2+. Increasing total dissolved organic carbon (DOC) concentrations of the NOM solution also resulted in an increase in the adsorption rates, likely due to divalent cation complexation with NOM carboxylate groups and the phosphate backbones of the DNA. The results from Fourier transform infrared spectroscopy (FTIR) for dissolved DNA and DNA adsorbed on silica beads also suggest that adsorption may result from divalent cation complexation with the DNA's phosphate backbone. The interactions, between DNA and NOM, however, did not influence natural transformation of Azotobacter vinelandii by DNA. These results suggest that DNA adsorbed to NOM-coated silica or otherwise complexed with NOM remains available for natural transformation in the environment.
AB - To better understand gene transfer in the soil environment, the interactions between dissolved natural organic matter (NOM) and chromosomal or plasmid DNA adsorbed to silica surfaces were investigated. The rates of NOM adsorption onto silica surfaces coated with DNA were measured by quartz crystal microbalance (QCM) and showed a positive correlation with carboxylate group density for both soil and aquatic NOM in solutions containing either 1mM Ca 2+ or Mg 2+. Increasing total dissolved organic carbon (DOC) concentrations of the NOM solution also resulted in an increase in the adsorption rates, likely due to divalent cation complexation with NOM carboxylate groups and the phosphate backbones of the DNA. The results from Fourier transform infrared spectroscopy (FTIR) for dissolved DNA and DNA adsorbed on silica beads also suggest that adsorption may result from divalent cation complexation with the DNA's phosphate backbone. The interactions, between DNA and NOM, however, did not influence natural transformation of Azotobacter vinelandii by DNA. These results suggest that DNA adsorbed to NOM-coated silica or otherwise complexed with NOM remains available for natural transformation in the environment.
KW - Adsorbed extracellular DNA
KW - Azotobacter vinelandii
KW - Environmental chemistry
KW - Natural gene transformation
KW - Natural organic matter
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U2 - 10.1016/j.scitotenv.2012.03.063
DO - 10.1016/j.scitotenv.2012.03.063
M3 - Article
C2 - 22542236
AN - SCOPUS:84860650859
SN - 0048-9697
VL - 426
SP - 430
EP - 435
JO - Science of the Total Environment
JF - Science of the Total Environment
ER -