Study finds decontamination can leave antibiotic resistance DNA functional

By AI, Created 9:51 AM UTC, May 20, 2026, /AGP/ – A J. Craig Venter Institute study in Cell Reports Methods says common lab disposal steps, including bleach and autoclaving, may not fully destroy engineered DNA carrying antibiotic resistance genes. The findings could shape biosafety guidance and push labs toward disposal practices that account for what survives after cells are killed.

Why it matters: - Antibiotic resistance genes are widely used as selectable markers in genetic engineering, so any surviving DNA raises a biosafety question for routine lab disposal. - The study suggests current decontamination practices may inactivate cells without fully eliminating recombinant DNA that can still function. - The findings could inform future disposal guidance and the development of antibiotic-free selection systems.

What happened: - Scientists at the J. Craig Venter Institute tested bleach treatment and autoclaving on bacterial cultures containing engineered DNA. - The work appears in Cell Reports Methods under the title “Resilience of recombinant antibiotic resistance gene-containing plasmids against common cell culture disposal methods.” - The researchers found that DNA recovered after decontamination could still transform bacteria in laboratory tests.

The details: - The team exposed cultures to bleach across a range of concentrations and contact times. - The team also tested autoclaving under commonly used conditions. - PCR and sequencing showed that antibiotic resistance gene sequences persisted after both disposal methods. - Laboratory gene-transfer models showed recovered DNA could still confer antibiotic resistance. - Standard bleach and autoclave treatment did not completely destroy antibiotic resistance genes carried on engineered DNA in the tested cultures. - Transformation outcomes varied by method and host. - The experiments used purified DNA recovered from treated cultures under ideal laboratory conditions. - The study did not track recombinant DNA in real waste streams. - The study did not provide direct evidence of environmental transfer from laboratory-derived DNA. - Funding came from the National Science Foundation, the National Institutes of Health, the U.S. Department of Agriculture, and the U.S. Environmental Protection Agency.

Between the lines: - The result does not show that lab waste is spreading resistant DNA into the environment. - The result does show biosafety assumptions may need to look beyond whether cells are alive after disposal. - As DNA synthesis and deployment become cheaper and more routine, the volume of labs using these plasmids is likely to grow. - JCVI framed the work as a biosafety improvement effort, not an alarm signal.

What’s next: - The authors say the data could support updated disposal guidance. - The findings may also encourage more use of selection systems that do not rely on antibiotic resistance markers. - JCVI says the study extends its policy and biosafety research on synthetic biology and DNA governance. - More information is available in the journal article and JCVI’s announcement.