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Quorum Sensing . Do Bacteria feel,sense and talk?. لا لما نلم اصحابنا ا لاول. يلا ناكل. Under Supervision of : Prof.Dr / Nabil Hegazy Presented by : Elshimaa Ali Shrouk Mohamed . Talking Bacteria.
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Quorum Sensing Do Bacteria feel,sense and talk? لا لما نلم اصحابنا الاول يلا ناكل Under Supervision of : Prof.Dr / Nabil Hegazy Presented by : Elshimaa Ali Shrouk Mohamed
Talking Bacteria • Woody Hastings and co-workers in 1970 first described quorum sensing in the marine bacteria Vibriofischeri. Symbiotic relationship
QS controlled processes Biofilm formation conjugation motility
Quorum Sensing in Nitrogen-Fixing Rhizobia Symbiotic relationship
QS in Grame negative bacteria acyl-homoserine lactones (AHL)
Great we talk the same language Different language
Quorum quenching • Interference of AHL-dependent QS. Interference of AHL destroy AHLs SignallingConfusion (lactonase and acylase ) (oxidoreductases ) (hydrolysis)
انا واخويا على ابن عمى وانا وابن عمى على الغريب bacteria produce QQ enzymes in competition for the limited natural resources. Ex (lactonases of B. thuringiensis has been shown to quench the virulence of the phytopathogenE. carotovora by inactivating its AHL signals) EX : pea and red alga produce compouds that interferance QS.
Now a days most of bacteria are antibiotic resistant New way to control certain bacterial infections By QQ
bacteria have 2 language (V. harveyi communication systems)
Cholera at low cell density surprisingly it turn on all of its vierulence genes. then at a high cell density when autoinducers accumulate cholera turn off virulence.
Biofilms are found almost everywhere in nature, including rivers, lakes, soil, water pipes, and even inside the human body. A common type of bacterial biofilm-responsible for plaque.
References http://www.mendeley.com/catalog/synthetic-furanones-inhibit-quorum-sensing-enhance-bacterial-clearance-pseudomonas-aeruginosa-lung-i/ • http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3376616/ http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3355433/ http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3376616/ • http://www.ncbi.nlm.nih.gov/pmc/articles/PMC309046/#!po=2.72727
تُسَبِّحُ لَهُ السَّمَاوَاتُ السَّبْعُ وَالأَرْضُ وَمَن فِيهِنَّ وَإِن مِّن شَيْءٍ إِلاَّ يُسَبِّحُ بِحَمْدَهِ وَلَـكِن لاَّ تَفْقَهُونَ تَسْبِيحَهُمْ إِنَّهُ كَانَ حَلِيماً غَفُوراً. [سورة الإسراء]