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bioRxiv · 10.1101/2022.05.26.493671

Ultraviolet Rate Constants of Pathogenic Bacteria: A Database of Genomic Modeling Predictions

Kowalski, W. J.·Bahnfleth, W.·Brais, N.·Walsh, T. J.
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Abstract

A database of bacterial ultraviolet (UV) susceptibilities is developed from an empirical model that correlates genomic parameters with UV rate constants. Software is used to count and evaluate potential ultraviolet photodimers and identifying hot spots in bacterial genomes. The method counts dimers that potentially form between adjacent bases that occur at specific genomic motifs such as TT, TC, CT, & CC. Hot spots are identified where clusters of three or more consecutive pyrimidines can enhance absorption of UV photons. The model incorporates nine genomic parameters into a single variable for each species that represents its relative dimerization potential. The bacteria model is based on a curve fit of the dimerization potential to the ultraviolet rate constant data for 92 bacteria species represented by 216 data sets from published studies. There were 4 outliers excluded from the model resulting in a 98% Confidence Interval. The curve fit resulted in a Pearson correlation coefficient of 80%. All identifiable bacteria important to human health, including zoonotic bacteria, were included in the database and predictions of ultraviolet rate constants were made based on their specific genomes. This database is provided to assist healthcare personnel and researchers in the event of outbreaks of bacteria for which the ultraviolet susceptibility is untested and where it may be hazardous to assess due to virulence. Rapid sequencing of the complete genome of any emerging pathogen will now allow its ultraviolet susceptibility to be estimated with equal rapidity. Researchers are invited to challenge these predictions. ImportanceThis research demonstrates the feasibility of using the complete genomes of bacteria to determine their susceptibility to ultraviolet light. Ultraviolet rate constants can now be estimated in advance of any laboratory test. The genomic methods developed herein allow for the assembly of a complete database of ultraviolet susceptibilities of pathogenic bacteria without resorting to laboratory tests. This UV rate constant information can be used to size effective ultraviolet disinfection systems for any specific bacterial pathogen when it becomes a problem.

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Kowalski, W. J., Bahnfleth, W., Brais, N., Walsh, T. J.. 2022-05-28. Ultraviolet Rate Constants of Pathogenic Bacteria: A Database of Genomic Modeling Predictions. https://doi.org/10.1101/2022.05.26.493671

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