Antisense inhibition of lpxB gene expression in Acinetobacter baumannii by peptide–PNA conjugates and synergy with colistin

1. JUAN JOSÉ GIRALDO SOTO
ESTUDIANTE DE MEDICINA
TERCER SEMESTRE 2020-1

2. INTRODUCTION
Acinetobacter baumannii
Growth inhibition of A.
baumannii by anti-gyrA PNAs has
been demonstrated
A. baumannii disease can cause
severe pneumonia and urinary
tract infections
gram-negative pathogenic
cocobacillus species
it is an important intrahospital
pathogen, difficult to treat due
to its resistance
Colistina
It is an antibiotic active against
various aerobic bacteria Gram-
causes nephrotoxicity and
neurotoxicity

3. INTRODUCTION
• This study evaluates the potential of anti-lpxB pPNA to convert the infection of
the bacterium using it with or without colistin.
Anti-lpxB pPNA Colsitin Acinetobacter baumannii

4. OBJECTIVES
To evaluate the lpxB gene in
Acinetobacter baumannii as a
potential therapeutic target
and to propose antisense
agents such as peptide nucleic
acids (PNAs) as a tool to
combat bacterial infection,
either alone or in combination
with known antimicrobial
therapies.

5. MATERIALES
Se utilizaron ceipas A. baumannii las
cuales se cultivaron a una
temperatura de 37 ° C en un medio
LB y tambien en un medio M9
Las células epiteliales alveolares
humanas A549 se mantuvieron a
37°C

6. MÉTODOS
¿PARA QUE SE UTILIZO?
comparó el ARN extraído de las bacterias que infectan los
pulmones de los ratones con el de las bacterias que crecen
in vitro
FUNDAMENTO
El fundamento de esta prueba es estudiar y comparar los
trascriptomas es decir, los conjuntos de ARNm que es están
presentes en una célula, tejido o organismo
ANALISIS
TRANSCRIPTOMICO
¿PARA QUE SE UTILIZO?
se utilizo para demostrar que el uso pPNA anti-lpxb reduce
la expresion de LpxB en el gen MUR y pra la expresion de
LpxB
FUNDAMENTO
Es una técnica analítica usada para detectar una proteína
especifica en función de su peso molecular mediante el uso
de anticuerpos
WESTERN BLOT

7. MÉTODOS
MIC
EL FUNDAMENTO de esta es analizar
la concentracion mas baja de de
antimicrobiano que que ihibe el
creciemiento de un microorganismo
despues de su incubacion
SE UTILIZO para evaluar dos
condiciones extremas con un exceso
y deficiencia de nutrientes
bacterianos en un medio LB y M9.
INHIBICION POR
PPNAS
(Time–kill analysis)
EL FUNDAMENTO de esta es medir el cambio
en una población de microorganismos
dentro de un tiempo específico después de
la exposición a un material de prueba
antimicrobiano y para comparar la
polaridad del ADN y ARN
SE UTILIZO para medir la actividad
bactericida in vitro de los pPNA anti-lpxB,
anti-murA y anti-hisF

8. RESULTADOS

9. RESULTADOS

10. RESULTADOS

11. DISCUSSION
AUTHOR WHAT DID HE SAY YES OR NO
Rasmussen LC, etal.
The emergence of bacterial resistance and the scarce arsenal of
antimicrobials available have led to an urgent need to design alter- native
strategies to combat infections caused by MDR pathogens. One approach as
a potential novel therapy against resistant pathogens is the use of
antisense molecules such as PNAs, BNAs and PMOs, which have shown
promising results and could, in time, become a new medical weapon
against MDR bacteria
Is fulfilled
Good L, etal.
Reducing the colistin dosage would be an excellent way to improve its use-
fulness. In this study, we tested the synergistic activity of colistin in
combination with anti-lpxB pPNA. The outer membrane of the bac- teria is
the first line of defence against PNA penetration
Is fulfilled
Hansen AM , etal.
Given the significant problem of MDR A. baumannii and the potential
benefits of pPNAs, we think that greater effort and attention should be
paid to the development of these new antibacterial agents. In recent
years, studies have investigated oligomers that target essential bacterial
genes conjugated to carrier peptides for delivery.
Is fulfilled

12. CONCLUSIONS
The LpxB gene is related to the
survival of Acinetobacter
baumannii, and that when using
an anti-lpxB pPNA, the gene will
not show an expression
It can be concluded that
the anti-lpxB pPNA had a
better antimicrobial effect
when combined with
colistin, since a synergy was
observed between both