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There are numerous other AMPs throughout the body. The characteristics of a few of the more significant AMPs are summarized in [link] .

Characteristics of Selected Antimicrobial Peptides (AMPs)
AMP Secreted by Body site Pathogens inhibited Mode of action
Bacteriocins Resident microbiota Gastrointestinal tract Bacteria Disrupt membrane
Cathelicidin Epithelial cells, macrophages, and other cell types Skin Bacteria and fungi Disrupts membrane
Defensins Epithelial cells, macrophages, neutrophils Throughout the body Fungi, bacteria, and many viruses Disrupt membrane
Dermicidin Sweat glands Skin Bacteria and fungi Disrupts membrane integrity and ion channels
Histatins Salivary glands Oral cavity Fungi Disrupt intracellular function
  • Why are antimicrobial peptides (AMPs) considered nonspecific defenses?

Plasma protein mediators

Many nonspecific innate immune factors are found in plasma , the fluid portion of blood. Plasma contains electrolytes, sugars, lipids, and proteins, each of which helps to maintain homeostasis (i.e., stable internal body functioning), and contains the proteins involved in the clotting of blood. Additional proteins found in blood plasma, such as acute-phase proteins, complement proteins, and cytokines, are involved in the nonspecific innate immune response.

Plasma versus serum

There are two terms for the fluid portion of blood: plasma and serum. How do they differ if they are both fluid and lack cells? The fluid portion of blood left over after coagulation (blood cell clotting) has taken place is serum . Although molecules such as many vitamins, electrolytes, certain sugars, complement proteins, and antibodies are still present in serum, clotting factors are largely depleted. Plasma, conversely, still contains all the clotting elements. To obtain plasma from blood, an anticoagulant must be used to prevent clotting. Examples of anticoagulants include heparin and ethylene diamine tetraacetic acid (EDTA). Because clotting is inhibited, once obtained, the sample must be gently spun down in a centrifuge. The heavier, denser blood cells form a pellet at the bottom of a centrifuge tube, while the fluid plasma portion, which is lighter and less dense, remains above the cell pellet.

Acute-phase proteins

The acute-phase proteins are another class of antimicrobial mediators. Acute-phase proteins are primarily produced in the liver and secreted into the blood in response to inflammatory molecules from the immune system. Examples of acute-phase proteins include C-reactive protein , serum amyloid A , ferritin , transferrin , fibrinogen , and mannose-binding lectin . Each of these proteins has a different chemical structure and inhibits or destroys microbes in some way ( [link] ).

Some Acute-Phase Proteins and Their Functions
C-reactive protein Coats bacteria (opsonization), preparing them for ingestion by phagocytes
Serum amyloid A
Ferritin Bind and sequester iron, thereby inhibiting the growth of pathogens
Transferrin
Fibrinogen Involved in formation of blood clots that trap bacterial pathogens
Mannose-binding lectin Activates complement cascade

Questions & Answers

fermented foods likely benefited ancestors to preserve foods and make other foods like milk, cheese, and bread using microbes.
Zinnia Reply
the evidence that I would support the statement regarding ancient people ideas that disease was transmitted by things they could not see is by the discoveries under a microscope. Many microbiologists have discovered certain diseases caused by microbes.
Zinnia
plz give the information about glyoxylate cycle
kamini Reply
what type of information?
Sapiens
I need medical microbiology mcqs books for Mbbs
Kisota
for pakistani mbbs or other?
Sapiens
what is microbial soup?
Osborn Reply
😃😂funny question isn't it?!!! sorry for inconvenience 😊
ayesha
most bacterial pathogens that cause disease in humans are classified in terms if their preferable ph as
Beesan Reply
what is micro
Kabul Reply
extremely small in size
Swetha
almost invisible to the naked eye
Peter
thanks
Sadiq
uwc
Peter
invisible sized objects
Sivasri
invisible sized object or specimens.which is used to see in only the microscope that specimens or objective called the micro
Sivasri
small organism that can be seen by use of Microbes
Manyang
why do you need to study microorganisms
Sala
what is microbiology?
Green Reply
microbiology is a branch of biology .it deals with the study of microorganisms life cycle , uses, disadvantages,and it impact in any other fields .which is used to view in microscope .
Sivasri
Microbiology is the study of microorganisms, those being unicellular, multicellular, or acellular. Microbiology encompasses numerous sub-disciplines including virology, bacteriology, protistology, mycology, immunology and parasitology. 
Raj
In short , it is the study of micro organisms and types , characteristics.
Kaviya
can you explain the structure of rna in detail
Dhanalakshmi Reply
RNA is of many types....like mRNA,tRNA,rRNA,snRNA,guideRNA..etc .
Swetha
but generally RNA is single stranded
Swetha
It contains adenine guanine cytosine , instead of thymine it contains uracil.
Swetha
ribonucleic acid present in RNA.. where as in DNA it is deoxyribonucleic acid...and ribonucleotide is present in RNA
Swetha
RNA is a blue print of DNA. it has the information from DNA....and we can predict the base panirs in DNA if we have the RNA....copy of that DNA
Swetha
can either have positive or negative polarity
Ernestine
Diatoms need..... With the help of which they can construct their beautiful cell wall
Prathmesh Reply
Microbial growth curve shows a.... Curve.
Shambhuraj Reply
diminishing curve
Oluwapamilerin
It represents the decreasing growth of an organism.
Swetha
what is meant by reverse isolation in tuberculosis treatment?
Swetha Reply
why do we study microbiology
HABIBA Reply
Microbiology is the way of gaining knowledge about those organisms which are surround us but we can't see them with our naked eye,such organisms called microorganisms..We can see them only under microscope.
ayesha
from our birth to death microorganisms are with us in the environment as well as on our body which are called Microflora.
ayesha
Microfloras are non pathogenic
ayesha
what is microbiology
Anji Reply
It is the study of microorganisms and their structures functions and their interactions with environment ...
Swetha
it is the study of microorganisms which are invisible to backed eye but we can see them under microscope then microbiology is the study of microorganisms including their structures , functions,and their interactions with environment
Swetha
tq
Anji
tqq...not backed eye sorry nacked eye
Swetha
it's ok
Anji
where r u from
Anji
thank you
Swetha
from India
Swetha
which state
Anji
Hyderabad .
Swetha
so telugu vosthadhi kadha
Anji
chelusu nakku kochum
Swetha
thank you
Swetha
what is reverse isolation in tuberculosis treatment?
Swetha
Reverse isolation is used to protect you from germs when your immune system is not working properly. Germs can be carried on droplets in the air, medical equipment, or another person's body or clothing.
Kaviya
will you repeat this again?
Swetha
Reverse isolationis used to protect you from germs when your immune system is not working properly. Germs can be carried on droplets in the air, medical equipment, or another person's body or clothing.
Kaviya
kill you?
Swetha
Y
Kaviya
nothing to see the whole answer that is why I sent u like that then only I can see the full answer la
Swetha
What is allosteric site?
Hetshree Reply
I don't know how to explain but it's a deep concave site of an enzyme it's slightly or more slightly similar to the active site on an enzyme
ayesha
a site other than enzyme active site
Muhammad
describe the gram staining procedure as used in identification and classification of bacteria and it's interpretation
tabitha Reply
Gram staining method found by Hans Christian Gram. Classified into Gram Positive and Gram Negative Positive would be purple or blue stained bacteria Negative would be Pink or Red stained bacteria Both are observed under microscope This procedure performed on glass slides by making a smear of sample.
ayesha
Thanks.. nicely u defined
shamim
jazakallah Khair
ayesha
hmmm
shamim
Masha allah
Khamis
jazakallah Khair
ayesha
hi
Nafiu
Heavy rains on Tuesday 21/1/20202 caused heavy floods on wednesday of 22/1/2020. Floods caused a lot of destruction including cut off of central corridor main road, property destruction and other problems including a single reported death. As a clinician you are asked to mention and explain 5 common health problems in all disasters.
Miryam Reply
Practice MCQ 5

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Source:  OpenStax, Microbiology. OpenStax CNX. Nov 01, 2016 Download for free at http://cnx.org/content/col12087/1.4
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