Innovative Methodology for Antimicrobial Susceptibility Determination in <i>Mycoplasma</i> Biofilms

<i>Mycoplasma</i> spp. are facultative pathogens that contribute to the pathogenesis of multiple bovine diseases, including the bovine respiratory disease complex, and have been shown to form biofilms. Biofilm formation is associated with increased antibiotic resistance in many organisms...

Full description

Saved in:
Bibliographic Details
Main Authors: B. Tegner Jacobson, Jessica DeWit-Dibbert, Eli T. Selong, McKenna Quirk, Michael Throolin, Chris Corona, Sobha Sonar, LaShae Zanca, Erika R. Schwarz, Diane Bimczok
Format: Article
Language:English
Published: MDPI AG 2024-12-01
Series:Microorganisms
Subjects:
Online Access:https://www.mdpi.com/2076-2607/12/12/2650
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1850060076165890048
author B. Tegner Jacobson
Jessica DeWit-Dibbert
Eli T. Selong
McKenna Quirk
Michael Throolin
Chris Corona
Sobha Sonar
LaShae Zanca
Erika R. Schwarz
Diane Bimczok
author_facet B. Tegner Jacobson
Jessica DeWit-Dibbert
Eli T. Selong
McKenna Quirk
Michael Throolin
Chris Corona
Sobha Sonar
LaShae Zanca
Erika R. Schwarz
Diane Bimczok
author_sort B. Tegner Jacobson
collection DOAJ
description <i>Mycoplasma</i> spp. are facultative pathogens that contribute to the pathogenesis of multiple bovine diseases, including the bovine respiratory disease complex, and have been shown to form biofilms. Biofilm formation is associated with increased antibiotic resistance in many organisms, but accurate determination of antimicrobial susceptibility in biofilms is challenging. In <i>Mycoplasma</i> spp., antimicrobial susceptibility is routinely determined using metabolic pH-dependent color change. However, biofilm formation can lead to reduced metabolism, making interpretation of metabolic readouts difficult. Therefore, we developed and optimized a new flow cytometry-based method for antimicrobial susceptibility testing in biofilm-forming <i>Mycoplasma</i>, termed the live/dead antimicrobial susceptibility test (LD-AST). The LD-AST measures the proportion of live bacteria upon exposure to antibiotics, works robustly with both planktonic and biofilm cultures, and enables the determination of the minimum bactericidal concentration (MBC) for a given antibiotic. We used two strains of <i>Mycoplasma bovis</i> (Donetta PG45 and Madison) and two clinical <i>Mycoplasma bovoculi</i> isolates (MVDL1 and MVDL2) to determine the impact of biofilm growth on antimicrobial susceptibility for gentamicin, enrofloxacin, or tetracycline. All <i>Mycoplasma</i> strains were susceptible to all antibiotics when cultured as planktonic cells, with MBCs in the expected range. However, three out of four strains (Donetta PG45, MVDL1, and MVDL2) were completely resistant to all three antibiotics when newly adhered biofilms were analyzed, whereas <i>M. bovis</i> Madison gave variable results. For mature biofilms that were cultured for 4–5 days before antibiotic exposure, results also were variable, with some strains showing an increased resistance with certain antibiotics and a decreased resistance with others. Overall, these results are consistent with earlier reports that biofilms can exhibit increased antimicrobial resistance.
format Article
id doaj-art-2d37b9d73d464ecab9632eeda99d37ea
institution DOAJ
issn 2076-2607
language English
publishDate 2024-12-01
publisher MDPI AG
record_format Article
series Microorganisms
spelling doaj-art-2d37b9d73d464ecab9632eeda99d37ea2025-08-20T02:50:41ZengMDPI AGMicroorganisms2076-26072024-12-011212265010.3390/microorganisms12122650Innovative Methodology for Antimicrobial Susceptibility Determination in <i>Mycoplasma</i> BiofilmsB. Tegner Jacobson0Jessica DeWit-Dibbert1Eli T. Selong2McKenna Quirk3Michael Throolin4Chris Corona5Sobha Sonar6LaShae Zanca7Erika R. Schwarz8Diane Bimczok9Department of Microbiology and Cell Biology, Montana State University, Bozeman, MT 59718, USADepartment of Microbiology and Cell Biology, Montana State University, Bozeman, MT 59718, USADepartment of Chemistry and Biochemistry, Montana State University, Bozeman, MT 59718, USADepartment of Microbiology and Cell Biology, Montana State University, Bozeman, MT 59718, USADepartment of Mathematical Sciences, Montana State University, Bozeman, MT 59718, USADepartment of Mathematical Sciences, Montana State University, Bozeman, MT 59718, USADepartment of Microbiology and Cell Biology, Montana State University, Bozeman, MT 59718, USADepartment of Microbiology and Cell Biology, Montana State University, Bozeman, MT 59718, USAMontana Veterinary Diagnostic Laboratory, Montana Department of Livestock, Bozeman, MT 59718, USADepartment of Microbiology and Cell Biology, Montana State University, Bozeman, MT 59718, USA<i>Mycoplasma</i> spp. are facultative pathogens that contribute to the pathogenesis of multiple bovine diseases, including the bovine respiratory disease complex, and have been shown to form biofilms. Biofilm formation is associated with increased antibiotic resistance in many organisms, but accurate determination of antimicrobial susceptibility in biofilms is challenging. In <i>Mycoplasma</i> spp., antimicrobial susceptibility is routinely determined using metabolic pH-dependent color change. However, biofilm formation can lead to reduced metabolism, making interpretation of metabolic readouts difficult. Therefore, we developed and optimized a new flow cytometry-based method for antimicrobial susceptibility testing in biofilm-forming <i>Mycoplasma</i>, termed the live/dead antimicrobial susceptibility test (LD-AST). The LD-AST measures the proportion of live bacteria upon exposure to antibiotics, works robustly with both planktonic and biofilm cultures, and enables the determination of the minimum bactericidal concentration (MBC) for a given antibiotic. We used two strains of <i>Mycoplasma bovis</i> (Donetta PG45 and Madison) and two clinical <i>Mycoplasma bovoculi</i> isolates (MVDL1 and MVDL2) to determine the impact of biofilm growth on antimicrobial susceptibility for gentamicin, enrofloxacin, or tetracycline. All <i>Mycoplasma</i> strains were susceptible to all antibiotics when cultured as planktonic cells, with MBCs in the expected range. However, three out of four strains (Donetta PG45, MVDL1, and MVDL2) were completely resistant to all three antibiotics when newly adhered biofilms were analyzed, whereas <i>M. bovis</i> Madison gave variable results. For mature biofilms that were cultured for 4–5 days before antibiotic exposure, results also were variable, with some strains showing an increased resistance with certain antibiotics and a decreased resistance with others. Overall, these results are consistent with earlier reports that biofilms can exhibit increased antimicrobial resistance.https://www.mdpi.com/2076-2607/12/12/2650antimicrobial resistance<i>Mycoplasma bovis</i><i>Mycoplasma</i> sp.biofilm formationflow cytometrylive/dead staining
spellingShingle B. Tegner Jacobson
Jessica DeWit-Dibbert
Eli T. Selong
McKenna Quirk
Michael Throolin
Chris Corona
Sobha Sonar
LaShae Zanca
Erika R. Schwarz
Diane Bimczok
Innovative Methodology for Antimicrobial Susceptibility Determination in <i>Mycoplasma</i> Biofilms
Microorganisms
antimicrobial resistance
<i>Mycoplasma bovis</i>
<i>Mycoplasma</i> sp.
biofilm formation
flow cytometry
live/dead staining
title Innovative Methodology for Antimicrobial Susceptibility Determination in <i>Mycoplasma</i> Biofilms
title_full Innovative Methodology for Antimicrobial Susceptibility Determination in <i>Mycoplasma</i> Biofilms
title_fullStr Innovative Methodology for Antimicrobial Susceptibility Determination in <i>Mycoplasma</i> Biofilms
title_full_unstemmed Innovative Methodology for Antimicrobial Susceptibility Determination in <i>Mycoplasma</i> Biofilms
title_short Innovative Methodology for Antimicrobial Susceptibility Determination in <i>Mycoplasma</i> Biofilms
title_sort innovative methodology for antimicrobial susceptibility determination in i mycoplasma i biofilms
topic antimicrobial resistance
<i>Mycoplasma bovis</i>
<i>Mycoplasma</i> sp.
biofilm formation
flow cytometry
live/dead staining
url https://www.mdpi.com/2076-2607/12/12/2650
work_keys_str_mv AT btegnerjacobson innovativemethodologyforantimicrobialsusceptibilitydeterminationinimycoplasmaibiofilms
AT jessicadewitdibbert innovativemethodologyforantimicrobialsusceptibilitydeterminationinimycoplasmaibiofilms
AT elitselong innovativemethodologyforantimicrobialsusceptibilitydeterminationinimycoplasmaibiofilms
AT mckennaquirk innovativemethodologyforantimicrobialsusceptibilitydeterminationinimycoplasmaibiofilms
AT michaelthroolin innovativemethodologyforantimicrobialsusceptibilitydeterminationinimycoplasmaibiofilms
AT chriscorona innovativemethodologyforantimicrobialsusceptibilitydeterminationinimycoplasmaibiofilms
AT sobhasonar innovativemethodologyforantimicrobialsusceptibilitydeterminationinimycoplasmaibiofilms
AT lashaezanca innovativemethodologyforantimicrobialsusceptibilitydeterminationinimycoplasmaibiofilms
AT erikarschwarz innovativemethodologyforantimicrobialsusceptibilitydeterminationinimycoplasmaibiofilms
AT dianebimczok innovativemethodologyforantimicrobialsusceptibilitydeterminationinimycoplasmaibiofilms