Safety, efficacy and utility of methods of transferring adhesive and cohesive Escherichia coli cells to microplates to avoid aerosols.
Ericksen. Bryan B
Key Findings
- The VCC assay can detect aerosol‑borne cross‑contamination in microplate experiments.
- A quantitative growth‑kinetics threshold (Tt) pinpoints when wells become inoculated.
- The method can be applied to both BSL‑1/2 and higher‑risk bacteria to improve safety.
Practical Outcomes
- If you run DIY microbiology or peptide‑testing experiments, this approach lets you monitor and reduce accidental aerosol spread, making your bench work safer. However, it doesn’t change how you would dose or use LL‑37 for health purposes.
Summary
The paper describes a lab technique for moving E. coli bacteria onto microplates without creating aerosol droplets, using a virtual colony count assay and a timing metric to spot contamination. It’s mainly about improving lab safety, not about how LL‑37 works in the body.
Abstract
The virtual colony count (VCC) microbiological assay has been utilized for over a decade to measure the antimicrobial activity of peptides such as defensins and LL-37 against biosafety level (BSL)-1 and BSL-2 bacteria including Escherichia coli, Staphylococcus aureus, Bacillus cereus, and Enterobacter aerogenes.  In addition, a modified pipetting technique was presented in a 2011 study of defensin activity against the BSL-3 pathogen Bacillus anthracis.  Both studies were published in the journal Antimicrobial Agents and Chemotherapy.  Here I report that the method can also detect cross-contamination caused by aerosols utilizing the VCC method of data analysis by quantitative growth kinetics (QGK).  The QGK threshold time, or T t, equivalent to the cycle time C t reported in 1996 by Heid et al., precisely identifies when wells were inoculated.
Study Information
pubmed
2014
2014-11-06T00:00:00.000Z
10.12688/f1000research.5659.2
3
13