Transcript Research Poster 24 x 36

The Evaluation Of Novel Βeta-Lactam Antibiotics On Clinical Bacterial Isolates.
Melvin
1
Grimes ,
Adrienne
1
Murphy ,Jason
Debra
of Biology, University of Louisiana at
Monroe,
2
Monroe,LA and School of Science and Technology , Nazarbayev University, Astana Kazakhstan
Abstract
The distribution and occurrence of multi-drug resistant
bacteria is an increasing public health problem. The
emergence of resistant bacteria makes the task of
synthesizing new antibiotics imperative to combating these
bacteria. In this study, the new beta-lactam antibiotics are
tested for broad spectrum activity using clinical E. coli and
Staphylococcus aureus strains. The clinical isolates were
grown over night and spread on Mueller Hinton (MH) agar.
The novel beta-lactam antibiotics were placed on sterile
disc and placed on the MH plates, incubated overnight,
and each zone of inhibition was measured. Our results
show several novel antibiotics are effective against the
clinical isolates.
2
Carr ,and
Materials and Methods
Strains: Clinical isolate of Escherichia
Staphylococcus aureus were used.
coli
Results
and
Media: Mueller Hinton Agar (MH) is used to test antibiotic
efficacy.
Novel Antibiotics Used: PDK94,Bis-2-pyridyl,HTS10,
3PD07, 3PDK08, Benzene Tellurinic (sodium salt),
2PDK42A,PDK 19, LEB 77,and LEB 78
Assay: Each antibiotic was suspended in 10 mls of 100%
ethanol. The clinical isolates were grown overnight then
diluted for the antibiotic disc assay. Each isolate was
spread on a MH agar plate in triplets. Sterile paper disc
were dipped in the antibiotic, placed on the plate, and
incubated at 37oC overnight. Each zone of inhibition was
measured.
Introduction
Beta-lactam antibiotics consist of a broad class of antibiotics
including penicillins, cephalosporins, carbapenems, and
monobactams. The mechanism of these antibiotics involves
the inhibition of cell wall synthesis by inactivating
transpeptidase an enzyme responsible for the cross linkage
of peptides of peptidoglycan. Both Staphylococcus aureus
and Escherichia coli are a part of the body’s normal flora
found on the skin and intestines respectively. In the case of S.
aureus an opportunistic pathogen, infections range from
minor skin infections such as pimples and boils to grave
illnesses such as endocarditis and toxic shock syndrome
(TSS). Many strains of E. coli can also cause disease and
illness in both the immunocompromised and the healthy.
E.coli can also produce toxins are responsible for several
food borne diseases such as E. coli 0157:H7. Additional
antimicrobial therapies against these organisms are needed.
This study was undertaken to test the efficacy of novel betalactams antibiotics against clinical Staph and E.coli
1
1
Jackson , Department
Zones of inhibition for Bis-2-pyridyl and Benzene
Tellurinic showing sensitivity toward the E. coli
Zones of inhibition for HTS10 and PDK 94 showing
sensitivity toward the E. coli.
Zones of inhibition for 3PDK07 and PDK19 showing sensitivity
toward the Staph. aureus
Zones of Inhibition for 3PDK08 and LEB78 showing
sensitivity toward the Staph. aureus
Zones of inhibition for Benzene Tellurinic and Bis-2-pyridyl showing
sensitivity toward the Staph. aureus
Conclusions
Results
Measured Zones of Inhibition
The data table shows the average zone of inhibition of the
antibiotic over three test trials and the standard deviation for
each antibiotic tested.
Antibiotics
Zone of Inhibition Average (mm)
HTS10
13±2
Bis-2-pyridyl
21±1
PDK 94
15±0
Bentel
22±2
Antibiotics
3PDK07
Zone of Inhibition Average (mm)
14±1.55
3PDK08
2PDK42A
PDK19
LEB 77
LEB 78
Benzene Telluric Acid
(sodium salt)
Bis-2-pyridyl
15±1.11
12±1.11
12±.44
10±.45
13±.67
16±1.34
• The E.coli isolates were sensitive toward the novel
antibotics Benzene tellurinic and Bis-2-pyridyl.
•The novel antibiotics PDK94 and HTS10 also proved to be
effective against the E.coli isolates
•The novel antibiotics 3PDK08,3PDK07,2PDK42A,and PDK
19,LEB77,LEB78,Benzene Tellurinic (sodium salt), and Bis2-pyridyl were most effective against Staph.aureus.
Future Direction
Additional clinical E. coli isolates and clinical Staphylococcoal
isolates will be tested for antibiotic susceptibility to the novel
beta-lactams presented here.
strains.
15±1.34
References
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The Microbial World :: A Look at All Things Small. Web. 29 Nov. 2011. <http://www.microbiologytext.edu/index.php?module=Book>.
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