The difference of gram positive and negative bacteria and bacteria species.

[Age12ProdigyofMicrobiology]

Gram staining/Gram positive vs. negative

 

When being a microbiologist, before you give your patient medicine to fight of their bacteria you need to know wether they have gram positive or negative bacteria. You need to know this because most medicines only serve the purpose to either gram negative or positive bacteria, for instiince penicillin does not kill gram negative bacteria. You find wether your patient has gram negative or positive bacteria by doing a gram stain. A gram stain is a Differentiating staining process for bacteria. Once completing the gram stain your gram positive bacteria will be purple , and gram negative bacteria will be pink under the microscope (if with correctly with oil immersion). A bacteria is either gram positive or negative based on its cell wall chemical composition. A gram positive bacteria has a thick pepditoglycan layer under the bacteria capsule, under the pepditoglycan a membrane similar to one humans have, in gram positive bacteria peptidoglycan there is teichoic acid, and lipoteichoic acid Under a gram negative bacterias capsule it has a membrain under that, a thin peptidoglycan layer, and another membrane. Sorry, my knowledge of negative bacterias chemical composition is not that wide.

 

Bacterium species

 

-Bacillus-some times called a "rod" a bacillus is a rectangle shaped bacteria.

 

-Coccus- a round circle shaped bacteria, there a different types of coccus too. There is the singular coccus that is is alone, the diplococci which is two cocci together the staphylococci means groups of cocci in irregular shapes, there is the streptococci which is three or more cocci in a strand, the sarcina which is two group of four cocci which a layered... in a way, and finally the tetrad which is a group of four cocci.

 

-Coccobacilli- an oval shaped bacteria inbbetween a coccus and a bacilli

 

-Vibrio- a spiral shaped bacteria

 

 

 

 

I am only 12 so there is no microbiology class, i rely on the internet, hopefully i will like this website and it helps me with my research and interests. if you have anything to add, or anything i messed up on or missed please tell me.

you can call me ..... Dr. Micro

 

[CharonY]

The description of the bacterial cell hull composition is slightly confusing.

In short, starting from the inside all bacteria have a cytoplasma membrane. This is followed by a peptidoglycan layer. The main difference at this point is that in Gram+ bacteria the peptidoglycan layer is much thicker. In both cases the sugar is made up from N-acetylglucosamine and N-acetylmuramic acid (linked to a short peptide), but in case of Gram+ more elements can be found within the thick layer, including S-layer on top and modified with glycopolymers throughout (which can quite diverse, depending on strain).

Gram- cells have an additional outer membrane just past their thin peptidoglycan layer.

 

Capsules are common, but not found in all bacteria and are often formed depending on growth conditions.

 

With regards to the morphologies, these are generally not used as species classification anymore. They are generally only used for rough classification with additional biochemical information available.

I congratulate your interest in this field and encourage you to get books on the subject as most websites are going to be awfully shallow and are unlikely to hold your interest for long. Or provide more comprehensive knowledge that is likely to provide deeper insights (eventually).

Edited August 27, 2013 by CharonY

[Age12ProdigyofMicrobiology]

The description of the bacterial cell hull composition is slightly confusing.

In short, starting from the inside all bacteria have a cytoplasma membrane. This is followed by a peptidoglycan layer. The main difference at this point is that in Gram+ bacteria the peptidoglycan layer is much thicker. In both cases the sugar is made up from N-acetylglucosamine and N-acetylmuramic acid (linked to a short peptide), but in case of Gram+ more elements can be found within the thick layer, including S-layer on top and modified with glycopolymers throughout (which can quite diverse, depending on strain).

Gram- cells have an additional outer membrane just past their thin peptidoglycan layer.

 

Capsules are common, but not found in all bacteria and are often formed depending on growth conditions.

 

With regards to the morphologies, these are generally not used as species classification anymore. They are generally only used for rough classification with additional biochemical information available.

I congratulate your interest in this field and encourage you to get books on the subject as most websites are going to be awfully shallow and are unlikely to hold your interest for long. Or provide more comprehensive knowledge that is likely to provide deeper insights (eventually).

I appreciate you sharing your knooledge with me and for your advice! I will be purchasing a a few books on microbio soon swell as staying a long term member ford this website.

[Titan1290]

Wow you know a lot! Bacteria belong to a kingdom called prokaryotes, they are prokaryotic cells. The word bacteria and prokaryotic is interchangeable biologists use say both words and they mean the same thing. Mammalian and plant cells belong to eukaryotes, they are eukaryotic cells. Some bacterial cells also have have flagellum which allows locomotion. Bacteria move by a process called chemotaxis basically the sense a nutrient and move towards it using the 'run and tumble' process (smelling food and you move to eat it!). The genome takes up most space inside the bacteria cell which contains most of the genetic material. There is also ringed structures called plasmids which contains a little genetic material. Some of these plasmids are the reason for antibiotic resistance! The space inside the prokaryotic cell is called the cytosol unlike the eukaryotic cell where it is called the cytoplasm. There is also Pili which is used in 'swapping' plasmids with other bacteria. There is also Fimbraie which is used for anchorage for the bacteria. The ribosome is where the bacteria makes proteins. The central dogma of biology is transcribing DNA into ---> mRNA which is translated into a ---> protein. The protein can be used for repair and growth for the bacteria. This is some additional information I hope it keeps you interested in microbiology and biology.

[CharonY]

Sorry, but the post has some serious errors that I feel I have to point out.

 

 

 

The word bacteria and prokaryotic is interchangeable

 

That is wrong, the term is not interchangeable. Prokaryotes include bacteria as well as archaea, both characterized by having no nucleus

 

 

 

Mammalian and plant cells belong to eukaryotes,

That is true but it is a weird distinction as eukaryotes obviously also covers all other animals as well as fungi.

 

 

 

move by a process called chemotaxis

Chemotaxis refers to directional movement not tot the means of movement. Also chemotaxis can be negative as well as positive (i.e. the chemical response is not only to nutrients) and there are other cues to which cells can respond.

 

 

 

The space inside the prokaryotic cell is called the cytosol unlike the eukaryotic cell where it is called the cytoplasm.

 

Also wrong, cytosol and cytoplasm are present in all cells. Cytosol essentially refers to the soluble part of the cytoplasm (in both cases).

 

There are also a number of minor inaccuracies or omission (e.g. depending on the type of pili they have a lot of different functions including movement and attachment). Or the fact that the genome is by definition the sum of all genetic material (chromosome+plasmids) and so on.