QUALITATIVE ANALYSIS OF PYOCYANIN ACTIVITY

AGAINST STREPTOCOCCUS PNEUMONIAE

Ali HashmiSummer Program 2011

Streptococcus pneumoniae

S. pneumoniae is a major cause of pneumonia, meningitis, and bacteremia in young children and adults

It is a normal flora of the human upper respiratory tract

Anaerobic member of the genus Streptococcus

How People Get Infected

Many people carry the bacteria in their upper respiratory system without becoming ill.

It is spread from person to person (Ex. Coughing, Sneezing, Inhaling etc).

It is not known why certain individuals develop invasive Streptococcus pneumoniae disease while others do not.

Pseudomonas aeruginosa

Widespread occurrence in water and in plant seeds

Most people with cystic fibrosis are likely to develop Pseudomonas aeruginosa infections by the time they are teenagers

Can cause lung, eye, ear, and skin infections; blood poisoning; urinary tract infections; wound infections

Pyocyanin

It is a metabolite produced by P. aeruginosa to kill cells, disrupts cilia actions, inhibits lymphocyte proliferation, and alters phagocyte function.

Gives out a blue-green tint color

Objective

Qualitatively analyze varying concentrations of pyocyanin against the growth of S. pneumoniae. 1 mg/mL .1 mg/mL .01 mg/mL .001 mg/mL

Method

1. Placed 50 µl of the different PCN concentration unto each mini-circle and 50 µl of dH20 as control.

2. Spotted 25 µl (1000CFU) of S.pneumoniae unto each mini-circle where PCN and dH20 was originally spotted, and dried before incubating for 16hrs

.001

.01

.1

1

dH20 + Sp

Sp

Method

1. In 50 mL of THY, 100 µl of each strain [mucoid and non-mucoid] was added into its respective tube

2. OD level was obtained every hour to determine growth of P. aeruginosa strains and pyocyanin production

Results

PCN 1mg/mL PCN 0.1mg/mL PCN 0.01mg/mL PCN 0.001mg/mL CONTROL0

20

40

60

80

100

120

140

CFU

/ml

Results

0 1 2 3 24-0.002

0.003

0.008

0.013

0.018

0.023

0.028

0.033

0.038

0

0.5

1

1.5

2

2.5

3

3.5

4

27318

Time (hr)

PC

N C

oncentr

ati

on

Od level

0 1 2 3 24-0.002

0.003

0.008

0.013

0.018

0.023

0.028

0.033

0.038

0

0.5

1

1.5

2

2.5

3

3.5

4

39324

Time (hr)

PC

N C

oncentr

ati

on

OD

level

Growth of P. aeruginosa

Pyocyanin production

Summary

S. pneumoniae is not sensitive to pyocyanin at physiologically relevant levels .

Pyocyanin was produced by both mucoid and non-mucoid strain, with higher amount by the mucoid strain.

Acknowledgments

Dr. MT CoatsEjoke EmemuRhonda BibbsKibiru Blythe