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Differences in cell wall of Gram positive and Gram negative Bacteria

What are superbugs and how can I protect myself from infection?
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What are superbugs and how can I protect myself from infection?
Answers from Pritish K. Tosh, M.D.
"Superbugs" is a term used to describe strains of bacteria that are resistant to the majority of antibiotics commonly used today. Resistant bacteria that cause pneumonia, urinary tract infections and skin infections are just a few of the dangers we now face.
Antibiotic resistance is a naturally occurring phenomenon that can be slowed, but not stopped. Over time, bacteria adapt to the drugs that are designed to kill them, and change to ensure their survival. This makes previously standard treatments for bacterial infections less effective, and in some cases, ineffective.
Certain actions may accelerate the emergence and spread of antibiotic-resistant bacteria, such as:
Using or misusing antibiotics
Having poor infection prevention and control practices
Living or working in unsanitary conditions
Mishandling food
To protect yourself from harmful bacteria, wash your hands often with soap and water, or use an alcohol-based hand sanitizer. Healthy lifestyle habits, such as eating a proper diet, proper food handling, getting enough exercise and establishing good sleeping patterns, can also minimize the risk of illness.
You can also help tackle antibiotic resistance by:
Using antibiotics as directed and only when needed
Completing the full treatment course, even if you feel better
Never sharing antibiotics with others
Never using leftover prescriptions

FLAGELLA STRUCTURE
The long helical filament of bacterial flagella is composed of many subunits of a single protein, flagellin, arranged in several intertwined chains. A flagellum consists of several components and moves by rotation, much like a propeller of a boat motor. The base of the flagellum is structurally different from the filament. The wider region at the base of the flagellum is called a hook. The hook connects the filament to the motor portion of the flagellum called a basal body.
The basal body is anchored in the cytoplasmic membrane and cell wall. It consists of a central rod that passes through a series of rings.
In gram-negative bacteria, three-set of rings are present in three different layers but gram-positive bacteria lack a lipopolysaccharide layer so the outer ring (L ring) is absent.

L- ring is anchored in the lipopolysaccharide layer.
P- ring is anchored in the peptidoglycan layer of
the cell wall.
M,S and C rings are located within the cytoplasmic membrane and the cytoplasm.
A series of proteins called Mot surrounds the inner pair of rings. These proteins actually drive the flagellar motor causing rotation of the filament. Another set of proteins called Fli proteins functions as the motor switch, reversing the rotation of the flagella in response to intracellular signals.
Arrangement and Types
Flagella are attached to cells in different places. As the number and location of flagella are distinctive for each genus, they can be used in the classification of bacteria. There are four types of flagellar arrangement.

Monotrichous (Mono means one): Single polar flagellum e.g. Vibrio cholerae, Campylobacter spp. (polar flagella often in pairs to give a “seagull” appearance).
Amphitrichous: Single flagellum at both ends e.g. Alcaligenes faecalis (note: amphibians live both on land and in water).
Lophotrichous: Tuft of flagella at one or both ends e.g. Spirilla spp
Peritrichous (flagella in the periphery): Flagella surrounding the bacterial cell. All the members of the family Enterobacteriaceae, if motile have peritrichous flagella. e.g. Salmonella Typhi, Escherichia coli, Proteus spp (highly motile organism; shows swarming motility)

Functions of Bacterial Flagella
Organs of locomotion: Many prokaryotes are motile, and the majority of motile prokaryotes move by means of flagella.
Role in Pathogenesis: Escherichia coli and Proteus spp are common causes of urinary tract infections. The flagella of these bacteria help the bacteria by propelling the bacteria from the urethra into the bladder.
Roles in Organism identification
Some species of bacteria, eg. Salmonella species are identified in the clinical laboratory by the use of specific antibodies against flagellar proteins.
Organisms such as Vibrio cholerae (darting motility) and Proteus species (swarming growth in common culture media) are easily identified by their characteristics motility pattern.