Project Title

Investigating the Relationship between Motility and Overproduction of Inhibitory Compound by Alcaligenes faecalis

Authors' Affiliations

Department of Health Sciences, College of Public Health, East Tennessee State University, Johnson City, TN

Location

Culp Ballroom

Start Date

4-7-2022 9:00 AM

End Date

4-7-2022 12:00 PM

Poster Number

108

Faculty Sponsor’s Department

Health Sciences

Name of Project's Faculty Sponsor

Sean Fox

Classification of First Author

Undergraduate Student

Competition Type

Competitive

Type

Poster Presentation

Project's Category

Microbiology

Abstract or Artist's Statement

Our laboratory has previously shown that Alcaligenes faecalis can inhibit both prokaryotic and eukaryotic microorganisms when competing for scarce resources. This mechanism requires A. faecalis to physically come into contact with the opposing microbe as opposed to a soluble secreted factor that it emits. A compelling possibility is A. faecalis utilizing a Type VI secretion system where a needle-like protrusion is inserted into the competing microbe. Once the protrusion is inserted, A. faecalis can release an inhibitory compound that can suppress the growth of the competing microbe. Using random transposon mutagenesis, ezTN5 was randomly inserted into A. faecalis’ genome to create mutants resulting in the expression of unique phenotypes. Mutants were screened against S. aureus to determine if the mutants were capable of producing the inhibitory compound or if the transposon successfully inserted into a gene responsible for the inhibitory component and thusly eliminating the ability to inhibit. A unique finding were mutants that demonstrated an ability to overproduce the inhibitory component while having minimal growth; however, other mutants had large growth with minimal production of the inhibitory compound. Still other mutants appeared to burrow into the agar rather than grow on top of it. To determine if the phenotypes seen in the differences in growth were significant, minimal growth/maximum inhibition mutants and maximum growth/minimal inhibition mutants were grown in 0.5% agar for motility potential. The growth of these mutants were then measured against wildtype A. faecalis to determine if there was significant differences in growth. To determine the ability of the mutants to over produce or under produce the inhibitory compound, 20µl of the mutants and 20 µl of wildtype of A. faecalis were grown on a lawn of S. aureus and the resulting phenotypes were compared. Utilizing race PCR, the genetic sequence of the mutants was obtained. Ultimately these experiments provide an interesting prospect of understanding the mechanisms behind this inhibition. This is the first step to potentially developing new therapeutic targets and also aid in the understanding of Alcaligenes polymicrobial behavior.

This document is currently not available here.

Share

COinS
 
Apr 7th, 9:00 AM Apr 7th, 12:00 PM

Investigating the Relationship between Motility and Overproduction of Inhibitory Compound by Alcaligenes faecalis

Culp Ballroom

Our laboratory has previously shown that Alcaligenes faecalis can inhibit both prokaryotic and eukaryotic microorganisms when competing for scarce resources. This mechanism requires A. faecalis to physically come into contact with the opposing microbe as opposed to a soluble secreted factor that it emits. A compelling possibility is A. faecalis utilizing a Type VI secretion system where a needle-like protrusion is inserted into the competing microbe. Once the protrusion is inserted, A. faecalis can release an inhibitory compound that can suppress the growth of the competing microbe. Using random transposon mutagenesis, ezTN5 was randomly inserted into A. faecalis’ genome to create mutants resulting in the expression of unique phenotypes. Mutants were screened against S. aureus to determine if the mutants were capable of producing the inhibitory compound or if the transposon successfully inserted into a gene responsible for the inhibitory component and thusly eliminating the ability to inhibit. A unique finding were mutants that demonstrated an ability to overproduce the inhibitory component while having minimal growth; however, other mutants had large growth with minimal production of the inhibitory compound. Still other mutants appeared to burrow into the agar rather than grow on top of it. To determine if the phenotypes seen in the differences in growth were significant, minimal growth/maximum inhibition mutants and maximum growth/minimal inhibition mutants were grown in 0.5% agar for motility potential. The growth of these mutants were then measured against wildtype A. faecalis to determine if there was significant differences in growth. To determine the ability of the mutants to over produce or under produce the inhibitory compound, 20µl of the mutants and 20 µl of wildtype of A. faecalis were grown on a lawn of S. aureus and the resulting phenotypes were compared. Utilizing race PCR, the genetic sequence of the mutants was obtained. Ultimately these experiments provide an interesting prospect of understanding the mechanisms behind this inhibition. This is the first step to potentially developing new therapeutic targets and also aid in the understanding of Alcaligenes polymicrobial behavior.