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Gram-negative

Gram-negative

(Science: microbiology) a common class of bacteria normally found in the gastrointestinal tract that can be responsible for disease in man (sepsis).

bacteria are considered to be gram-negative because of their characteristic staining properties under the microscope, where they either do not stain or are decolourised by alcohol during grams method of staining.

this is a primary characteristic of bacteria that have a cell wall composed of a thin layer of peptidoglycan covered by an outer membrane of lipoprotein and lipopolysaccharide containing endotoxin.

The gram staining characteristics of bacteria have resulted in an important classification system for the identification of bacteria.

See: gram-positive


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Streptococcus sanguis??

Hey guys have i correctly matched up my micro - organism? Gram reaction:+ Shape: cocci Acid-fast: - Spores: - Motility: - Grows in air: + Grows anaerobically: + Catalase: - Oxidase: - Acid from glucose: + OF test: : F Gas from glucose: - Acid from sucrose: ...

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by microbiologyhelp
Fri Dec 20, 2013 10:08 pm
 
Forum: Microbiology
Topic: Streptococcus sanguis??
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Views: 807

ID OF UNKNOWN?!?!

Hey guys, I'm needing help trying to identify my organism in microbiology classes, so far the results obtained indicate Gram reaction:+ Shape: cocci Acid-fast: - Spores: - Motility: - Grows in air: + Grows anaerobically: + Catalase: - Oxidase: - Acid from glucose: + OF test: : F Gas ...

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by microbiologyhelp
Fri Dec 06, 2013 10:59 am
 
Forum: Microbiology
Topic: ID OF UNKNOWN?!?!
Replies: 5
Views: 1358

Re: Bacterial Taxonomy

... the cell that serve a common function—but hami are "barbed" helical projections with hooked tips. I don't know how an archaean would Gram stain.

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by wildfunguy
Tue Dec 03, 2013 12:21 am
 
Forum: Microbiology
Topic: Bacterial Taxonomy
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Using oxidizing agents in gram stain

Considering the fact that Iodine is an oxidizing agent, what would happen if I replaced iodine with another oxidizing agent during the gram staining process ? So far I know that the purpose of the iodine is to form a complex with the crystal violet in order to enable the cell wall of the ...

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by ccBiologist
Sun Sep 22, 2013 2:44 pm
 
Forum: Microbiology
Topic: Using oxidizing agents in gram stain
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Views: 851

gram negative cocci. please help

You should have done a gram stain ...

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by sampei
Tue May 28, 2013 2:46 pm
 
Forum: Microbiology
Topic: gram negative cocci. please help
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Views: 7993
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