البكتيريا المضيئة

هناك انواع من البكتيريا المضئية؟؟؟؟؟؟؟
اذكر بعض اسماء و اذكر كيف تقوم بعملية الاضاءة و هل يمكن الاستفادة منها و لا لا؟؟؟؟؟؟
عزلها سهل للي عندهم بحر......... و اذا ما عندهم برضه ممكن......

علشان اسهل عملية البحث
Luminescent bacteria
و هاي صورة

Luminescent bacteria can be isolated from sea-water and from sea-fishes. This is the method of isolation of luminescent bacteria from fish:

The sea-fish body should be partially plunged in the salt solution (or sea-water) and stored in the refrigerator (in the temperature 4 - 6°C). After certain time the colonies of luminous bacteria will grow on the surface of fish body. These colonies can be isolated to obtain pure cultures.

(on the base of book "Mokrobiologia ogolna" by H. G. Schleger)

I must say, that I have not applied this method yet and I don't know if this method is effective.


Some of luminescent bacteria can live in symbiosis with marine organisms. For example some species of deep-sea fishes and cuttle-fishes have luminous organs in which luminous bacteria live.



Luminous bacteria can grow in more unusual places too:


A Canadian was in the mood for a late night snack but lost his appetite when he discovered that the snack was glowing in the dark.
This man was about to eat a piece of imitation crab meat in his darkened kitchen when he noticed the eerie blue-green luminescence.
"I ate a chunk in the daytime and there was nothing wrong," the man said.
A Health Canada food inspector found a luminescent type of bacteria to be the cause for this bizarre incident.


Decaying sea-fishes are natural rich medium for luminous bacteria.They can grow on the stored fishes.


At least one instance of a light producing strain from a wound has been reported.


Passengers on board cruise liners are sometimes startled by an eerie phosphorescent glow emitted by seawater flush lavatories. The explanation lies in luminous bacteria, which can find good terms to grow in such places.

The morphology and physiology researches showed that luminescent bacteria are very similar to enteric bacteria.

It is possible to observe the shape of luminescent bacteria cells using popular light microscope. The bacterial cells are more visible when special method of staining is used. There are many methods of staining. I used the Gram staining method and the negative staining method.

Every luminescent bacteria are Gram-negative. Bacterial cells have motion organs - flagella (they are visible in light microscope only when special method of staining is used). In the case of Vibrio genus polar flagella are enclosed in a sheath continuous with the outer membrane of the cell wall. In the case of Photobacterium genus only unsheathed flagella are present.

The luminescence ability is in strict dependence on the medium composition. The light generating reactions require oxygen. The luminescence process is something like the offshoot of the aerobic respiration. The main difference is that the final product of aerobic respiration is ATP and the final product of luminescence reactions is excited luciferase (chemical compound) which can generate light.

Luminescent bacteria are divided into two genera: Photobacterium and Vibrio. The best characterised species are:

Photobacterium phosphoreum*
Photobacterium luciferum
Vibrio fischeri
Vibrio harveyi

أتمنى أني أكون رديت صح على الموضوع

كفيت و فيت أخ غسان

بقى ان نعرف ما هي استخدامات هذه البكتيريا

البكتيريا المضيئة ستعمل على مضاعفة قدرة العقاقير على قتل خلايا الأورام الخبيثة مليون مرة كولون

Natural environment

Luminescent bacteria can be isolated from sea-water and from sea-fishes. This is the method of isolation of luminescent bacteria from fish:

The sea-fish body should be partially plunged in the salt solution (or sea-water) and stored in the refrigerator (in the temperature 4 - 6°C). After certain time the colonies of luminous bacteria will grow on the surface of fish body. These colonies can be isolated to obtain pure cultures.

(on the base of book "Mokrobiologia ogolna" by H. G. Schleger)

I must say, that I have not applied this method yet and I don't know if this method is effective.


Some of luminescent bacteria can live in symbiosis with marine organisms. For example some species of deep-sea fishes and cuttle-fishes have luminous organs in which luminous bacteria live.



Luminous bacteria can grow in more unusual places too:


A Canadian was in the mood for a late night snack but lost his appetite when he discovered that the snack was glowing in the dark.
This man was about to eat a piece of imitation crab meat in his darkened kitchen when he noticed the eerie blue-green luminescence.
"I ate a chunk in the daytime and there was nothing wrong," the man said.
A Health Canada food inspector found a luminescent type of bacteria to be the cause for this bizarre incident.


Decaying sea-fishes are natural rich medium for luminous bacteria.They can grow on the stored fishes.


At least one instance of a light producing strain from a wound has been reported.


Passengers on board cruise liners are sometimes startled by an eerie phosphorescent glow emitted by seawater flush lavatories. The explanation lies in luminous bacteria, which can find good terms to grow in such places.

Methods for the isolation and identification of a toxicant in a sample are disclosed. Luminescent biological agents (i.e., bacteria) having sensitivity to a toxicant or an isolatable component in a sample are used to provide visually discernable zones of luminescent inhibition in the presence of a toxicant (or) in the presence of an isolatable sample component as separated by paper or thin layer chromatography. Kits for use in conjunction with the identification of a toxicant in a sample are also described, which include a luminescent biological reagent as the visualizing agent. Particular examples of luminescent bacterial agents useful in the practice of the present invention include Photobacterium leoganthi, Photobacterium phosphoreum, Vibrio fischeri, Vibrio harveyi a luminescent fungi, a luminescent fish extract, a luminescent dinoflagellate and fluorescent microorganisms, such as Cypridina. Potential toxicants in a liquid sample, a solid sample, or in a gaseous sample may be identified and further chemically characterized using the described methods. The isolation of potential toxicants in a sample through the processing of a sample through a separation phase matrix such as chromatography paper or TLC plate, followed by exposure to luminescent biological agent, provides for a rapid and inexpensive method for identifying pesticides, herbicides and heavy metals in a known or unknown sample.

Species

Luminescent bacteria are divided into two genera: Photobacterium and Vibrio. The best characterised species are:

Photobacterium phosphoreum*
Photobacterium luciferum
Vibrio fischeri
Vibrio harveyi

I obtain these species from Department of Microbiology of University of Gdansk.

* - this bacterium was reclassified - now it is known as Vibrio phosphoreum

Cultivation and storage

Storage

Luminescent bacteria can be stored as standard glycerol stab cultures.
This is the method of preparing glycerol stab cultures of bacteria:

In the sterile plastic tube mix 0,15 ml sterilised glycerol and 0,85 ml liquid culture of luminescent bacteria
Shake the mixture well
The mixture should be frozen immediately using liquid nitrogen
Store the cultures in the temperature of -70°C
Cultivation of Luminescent Bacteria

Cultivation of luminous bacteria is processed on the special medium "BOSS"
This is the method of preparation the medium "BOSS":

30 g NaCl
1 g Glycerol
10 g Peptone (Bacto-Peptone)
3 g Beef Extract
(to obtain solid medium you should add 15 g of Bacto-Agar)
Dilute the ingredients in water (pH should be about 7,3)
Fill with H2O up till 1000 ml

There are some additional microbiological media used for cultivation of luminescent bacteria:

MICROBIOLOGICAL MEDIA FOR CULTIVATION OF LUMINESCENT BACTERIA


The cultivation should be conducted in temperature 18 - 22°C. Liquid cultures should be well aerated (the aeration pumps may be used or cultures should be shaken well). It is necessary to support sufficient amount of oxygen needed in luminescence reactions.


1.
2.


The photos above show liquid culture of luminescent bacterium - Photobacterium luciferum.
When we observe the culture of luminous bacteria in well lit place the light emitted by bacteria is not visible (photo 1). If we observe the same culture in the darkness the intensity of glowing is unbelievable (photo 2). Some of my friends connect this green light with UFOs.
It is interesting to point out that in order to take the photos (particularly photo 2) I had to support constant movement of the broth. If the culture was not mixed the intensity of growing was dropping drastically in some seconds - probably it was caused by lack of oxygen. I solved the problem by using magnetic stirrer.
(click on the photo to see it better)

On solid medium the most intensive glowing can be observed 1 - 5 days after inoculation but faint glowing can be observed longer (even some weeks). Big differences between different species of luminescent bacteria can be observed here (from my observation it occured that the shortest time of glowing have the luminescent bacterium - Vibrio harveyi).


1.
2.


Both pictures show the same culture of luminescent bacterium - Vibrio fischeri on the petri plates with medium "BOSS". Photo 1 was taken with regular light whereas photo 2 I took in darkness giving it long time of exposure.
(click on the photo to see it better)





The above photos show cultures of luminescent bacterium - Photobacterium phosphoreum on petri plates with medium "BOSS". The cultures was started soon before Christmas'97. As you can see we can obtain interesting effects streaking bacteria in such a way that after incubation

LA medium


Comment: This is the standard medium for cultivation of many bacteria species (e.g. Escherichia coli). The grow rate of luminous bacteria on this medium is fast although the grow rate on BOSS medium appears to be a little faster. I recommend this medium because it is the most commonly used microbiological medium (If you have it in your lab there is no need to prepare a special medium for cultivation of luminescent bacteria). In the case of Photobacterium phosphoreum I even observed the more intensive luminescence of culture growing on this medium than the culture growing on the BOSS medium.



BOSS medium

30 g NaCl
1 g Glycerol
10 g Peptone (Bacto-Peptone)
3 g Beef Extract
(to obtain solid medium you should add 15 g of Bacto-Agar)
Dilute the ingredients in water (pH should be about 7,3)
Fill with H2O up till 1000 ml


Comment: This is the special microbiological medium used for cultivation of luminescent bacteria. The grow rate of luminescent bacteria on this medium is fast and good intensity of luminescence is observed.

Medium for cultivation of luminescent bacteria
on the basis of materials from National Centre for Biotechnology Education

Yeast Extract 3 g
Peptone (Bacto-peptone) 5 g
Distilled water 250 ml
Sea water 750 ml


Comment: You can use the artificial sea water from one of the biological suppliers.


LM (Luminescence Medium)

Yeast Extract 5 g
Glycerol 3 ml
CaCO3 (powdered limestone or chalk) 1 g
Tryptone 5 g
Sea water fill up till 1000 ml


Comment: You can use the artificial sea water from one of the biological suppliers.

LA medium

NaCl
Yeast Extract
Peptone (Bacto-peptone)
Agar
Fill with H2O up till 1000 ml
10 g
5 g
10 g
15 g


Comment: This is the standard medium for cultivation of many bacteria species (e.g. Escherichia coli). The grow rate of luminous bacteria on this medium is fast although the grow rate on BOSS medium appears to be a little faster. I recommend this medium because it is the most commonly used microbiological medium (If you have it in your lab there is no need to prepare a special medium for cultivation of luminescent bacteria). In the case of Photobacterium phosphoreum I even observed the more intensive luminescence of culture growing on this medium than the culture growing on the BOSS medium.

BOSS medium

شكرا للمرور و المشاركة
هذه صورة لبكتيريا مضيئة تم عزلها من قبل طالبات التحاليل بالجامعة الاسلامية من عينات مياه بحر

هاي البكتيريا سمعت انو من التطبيقات اللي استفادو ومنها واخذو فكرة استخدام الانابيب المضيئة في الحفلات وهي عبارة عن ابنوبتين في داخل بعضهم يفصل بينهم مادة . والانبوبة اللي بالداخل موجود فيها الانزيم المأخوذ من البكتيريا المسؤول عن الاضاءة ,عند كسر الانبوبة فان المادة تختلط بالانزيم ويخرج اللون المضيئ ,يكون عادة باللون الاخضر الفسفوري او السماوي الفاقع .
هيك سمعت مرة وهاي كل اللي عندي.
شكرا.

اعتقد هذا لنوع من البكتيريا يعمل Qurum Sensing حيث لا يعطي اللون حتى يصل داخل الطبق الى عدد معين

صحيح بالنسبة ل quorum sensing

و يبدو ان الكثير من البكتيريا تخضع لهذه الظاهرة و يناءأ عليه فان فكرة الخلايا المنفردة مصانع منفردة أصبحت في حكم الخطأ و النظرية الاكثر قبولاً الان ان الخلايا المنفردة تعمل ككائن متعدد الخلايا من حيث التنسيق في الوظائف

هذا رابط لمحاضرة بوربوينت عن موضوع quorum sensing و كان التركيز فيها على الية العمل في البكتيريا المضيئة. أتمنى ان تفيد في الموضعين ذات العلاقة

http://www.esnips.com/nsdoc/d827bee8-555b-4453-abdd-950f1f328453

يعتمد هذا على نظام يسمى two componant regulatory system
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