Limits...
Extracellular DNA is essential for maintaining Bordetella biofilm integrity on abiotic surfaces and in the upper respiratory tract of mice.

Conover MS, Mishra M, Deora R - PLoS ONE (2011)

Bottom Line: We show that DNA is a significant component of Bordetella biofilm matrix.In conclusion, these results suggest that eDNA is a crucial structural matrix component of both in vitro and in vivo formed Bordetella biofilms.This is the first evidence for the ability of DNase I to disrupt bacterial biofilms formed on host organs.

View Article: PubMed Central - PubMed

Affiliation: Program in Molecular Genetics, Wake Forest University Health Sciences, Winston-Salem, North Carolina, United States of America.

ABSTRACT
Bacteria form complex and highly elaborate surface adherent communities known as biofilms which are held together by a self-produced extracellular matrix. We have previously shown that by adopting a biofilm mode of existence in vivo, the gram negative bacterial pathogens Bordetella bronchiseptica and Bordetella pertussis are able to efficiently colonize and persist in the mammalian respiratory tract. In general, the bacterial biofilm matrix includes polysaccharides, proteins and extracellular DNA (eDNA). In this report, we investigated the function of DNA in Bordetella biofilm development. We show that DNA is a significant component of Bordetella biofilm matrix. Addition of DNase I at the initiation of biofilm growth inhibited biofilm formation. Treatment of pre-established mature biofilms formed under both static and flow conditions with DNase I led to a disruption of the biofilm biomass. We next investigated whether eDNA played a role in biofilms formed in the mouse respiratory tract. DNase I treatment of nasal biofilms caused considerable dissolution of the biofilm biomass. In conclusion, these results suggest that eDNA is a crucial structural matrix component of both in vitro and in vivo formed Bordetella biofilms. This is the first evidence for the ability of DNase I to disrupt bacterial biofilms formed on host organs.

Show MeSH

Related in: MedlinePlus

DNase I leads to the disruption of established Bordetella biofilms grown on glass coverslips under static conditions.Biofilms were grown on glass coverslips for 48h for RB50 (A) and 96 h for Bp536 (B). The coverslips were gently rinsed followed by treatment with DNase I for either 30min or 90min. The cells were tagged with GFP and thus are green. For each micrograph, the middle panel represents the x-y plane, and the adjacent top and side panels represent the x-z and y-z planes, respectively. The images of a biofilm not treated with DNase I and treated only with DNase I buffer are also depicted. CLSM was utilized to image the biofilms.
© Copyright Policy
Related In: Results  -  Collection


getmorefigures.php?uid=PMC3037945&req=5

pone-0016861-g004: DNase I leads to the disruption of established Bordetella biofilms grown on glass coverslips under static conditions.Biofilms were grown on glass coverslips for 48h for RB50 (A) and 96 h for Bp536 (B). The coverslips were gently rinsed followed by treatment with DNase I for either 30min or 90min. The cells were tagged with GFP and thus are green. For each micrograph, the middle panel represents the x-y plane, and the adjacent top and side panels represent the x-z and y-z planes, respectively. The images of a biofilm not treated with DNase I and treated only with DNase I buffer are also depicted. CLSM was utilized to image the biofilms.

Mentions: To visualize the effect of DNase I on impacting biofilm structure, we continued this experiment with biofilms of GFP-expressing cells formed on glass coverslips in biphasic cultures. For B. bronchiseptica, the biofilms were grown for 48h followed by incubation with or without DNase I for either 30 or 90 minutes. In the absence of DNase I, the glass coverslip was extensively colonized resulting in the visualization of a thick layer of cells at the air-liquid interface (Fig. 4A). DNase I treatment for 30 min led to the dissolution of the preformed bacterial films and the cells existed in patchy localized clusters (Fig. 4A). On longer incubation with DNase I, we found that large areas of the coverslips were essentially devoid of bacterial cells, suggesting significant detachment of the biofilm biomass (Fig. 4A).


Extracellular DNA is essential for maintaining Bordetella biofilm integrity on abiotic surfaces and in the upper respiratory tract of mice.

Conover MS, Mishra M, Deora R - PLoS ONE (2011)

DNase I leads to the disruption of established Bordetella biofilms grown on glass coverslips under static conditions.Biofilms were grown on glass coverslips for 48h for RB50 (A) and 96 h for Bp536 (B). The coverslips were gently rinsed followed by treatment with DNase I for either 30min or 90min. The cells were tagged with GFP and thus are green. For each micrograph, the middle panel represents the x-y plane, and the adjacent top and side panels represent the x-z and y-z planes, respectively. The images of a biofilm not treated with DNase I and treated only with DNase I buffer are also depicted. CLSM was utilized to image the biofilms.
© Copyright Policy
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC3037945&req=5

pone-0016861-g004: DNase I leads to the disruption of established Bordetella biofilms grown on glass coverslips under static conditions.Biofilms were grown on glass coverslips for 48h for RB50 (A) and 96 h for Bp536 (B). The coverslips were gently rinsed followed by treatment with DNase I for either 30min or 90min. The cells were tagged with GFP and thus are green. For each micrograph, the middle panel represents the x-y plane, and the adjacent top and side panels represent the x-z and y-z planes, respectively. The images of a biofilm not treated with DNase I and treated only with DNase I buffer are also depicted. CLSM was utilized to image the biofilms.
Mentions: To visualize the effect of DNase I on impacting biofilm structure, we continued this experiment with biofilms of GFP-expressing cells formed on glass coverslips in biphasic cultures. For B. bronchiseptica, the biofilms were grown for 48h followed by incubation with or without DNase I for either 30 or 90 minutes. In the absence of DNase I, the glass coverslip was extensively colonized resulting in the visualization of a thick layer of cells at the air-liquid interface (Fig. 4A). DNase I treatment for 30 min led to the dissolution of the preformed bacterial films and the cells existed in patchy localized clusters (Fig. 4A). On longer incubation with DNase I, we found that large areas of the coverslips were essentially devoid of bacterial cells, suggesting significant detachment of the biofilm biomass (Fig. 4A).

Bottom Line: We show that DNA is a significant component of Bordetella biofilm matrix.In conclusion, these results suggest that eDNA is a crucial structural matrix component of both in vitro and in vivo formed Bordetella biofilms.This is the first evidence for the ability of DNase I to disrupt bacterial biofilms formed on host organs.

View Article: PubMed Central - PubMed

Affiliation: Program in Molecular Genetics, Wake Forest University Health Sciences, Winston-Salem, North Carolina, United States of America.

ABSTRACT
Bacteria form complex and highly elaborate surface adherent communities known as biofilms which are held together by a self-produced extracellular matrix. We have previously shown that by adopting a biofilm mode of existence in vivo, the gram negative bacterial pathogens Bordetella bronchiseptica and Bordetella pertussis are able to efficiently colonize and persist in the mammalian respiratory tract. In general, the bacterial biofilm matrix includes polysaccharides, proteins and extracellular DNA (eDNA). In this report, we investigated the function of DNA in Bordetella biofilm development. We show that DNA is a significant component of Bordetella biofilm matrix. Addition of DNase I at the initiation of biofilm growth inhibited biofilm formation. Treatment of pre-established mature biofilms formed under both static and flow conditions with DNase I led to a disruption of the biofilm biomass. We next investigated whether eDNA played a role in biofilms formed in the mouse respiratory tract. DNase I treatment of nasal biofilms caused considerable dissolution of the biofilm biomass. In conclusion, these results suggest that eDNA is a crucial structural matrix component of both in vitro and in vivo formed Bordetella biofilms. This is the first evidence for the ability of DNase I to disrupt bacterial biofilms formed on host organs.

Show MeSH
Related in: MedlinePlus