MDS PREP
There are some enzymes that cause protein to coagulate rather than to produce simpler compund These are known as
1. lab enzymes
2. coagulase
3. proteolytic enzymes
4. wenmycin
Microbiology
Answer: 1
There are some enzymes that cause protein to coagulate rather than to produce simpler compund These are known as lab enzymes
1. Coagulase:
Definition: Coagulase is an enzyme produced by certain
bacteria, most notably Staphylococcus aureus. It catalyzes the
conversion of fibrinogen (a soluble plasma protein) into fibrin (an
insoluble protein), leading to the clotting of blood.
Function: The production of coagulase is a virulence
factor for Staphylococcus aureus, as it helps the bacteria evade
the host's immune system by forming a protective clot around the bacterial
cells. This clot can shield the bacteria from phagocytosis and other immune
responses.
Clinical Relevance: Coagulase is used in laboratory
tests to differentiate between pathogenic Staphylococcus aureus (coagulase-positive)
and non-pathogenic staphylococci (coagulase-negative).
2. Proteolytic Enzymes:
Definition: Proteolytic enzymes, also known as
proteases or peptidases, are enzymes that catalyze the breakdown of proteins
into smaller peptides or amino acids by cleaving the peptide bonds between
amino acids.
Function: These enzymes play crucial roles in various
biological processes, including digestion, protein turnover, cell signaling,
and immune responses. They are found in many organisms, including humans,
where they are involved in the digestion of dietary proteins in the stomach
and small intestine.
Types: Proteolytic enzymes can be classified based on
their mechanism of action (e.g., serine proteases, cysteine proteases,
aspartic proteases, and metalloproteases) and their substrate specificity.
Wenmycin is an antibiotic that is derived from the
bacterium Streptomyces wenyangensis. It belongs to the class of
compounds known as macrolide antibiotics, which are
characterized by their large lactone ring structure. Wenmycin has been studied
for its antimicrobial properties, particularly against certain types of
bacteria.
What is the significance of "Rose spots" in typhoid fever?
1) They indicate the presence of a complication such as intestinal perforation.
2) They are a diagnostic sign of typhoid fever.
3) They indicate the patient is no longer infectious.
4) They indicate the patient has developed antibodies to the bacterium.
General Microbiology Answer: 2The presence of "Rose spots" can
help in diagnosing typhoid fever, as they are relatively specific to this
illness. They typically appear in the trunk and are not a result of increased
sensitivity to the touch or pressure.
Which of the following is true about the fermentation characteristics of Bacillus anthracis?
1) Ferments salicin
2) Produces H2S abundantly
3) Ferments glucose, maltose, lactose, and sucrose
4) All of the above
Bacillus anthracis ferments glucose, maltose, lactose, and sucrose, but does not ferment salicin or produce H2S abundantly.
What is the primary reservoir for prions?
1) Bacteria
2) Viruses
3) Proteinaceous particles
4) Nucleic acids
General Microbiology Answer: 3Prions are infectious agents composed solely of protein. They do not have nucleic acids like DNA or RNA and are responsible for several neurodegenerative diseases. The primary reservoir for prions is thus the proteinaceous particles themselves.
What is the purpose of using aluminum hydroxide as an adjuvant in the hepatitis B vaccine?
1) To increase the immunogenicity of the vaccine
2) To prevent bacterial contamination
3) To enhance the stability of the vaccine
4) To reduce the amount of antigen needed for immunization
General Microbiology Answer: 1
Aluminum hydroxide is used as an adjuvant in the hepatitis B vaccine to increase the immunogenicity of the vaccine, enhancing the body's immune response to the antigen.
What is the primary clinical significance of a deficiency in C5 to C8 components of the complement system?
1) Hereditary angioneurotic edema
2) Recurrent pyogenic infections
3) Systemic lupus erythematosus
4) Neisserial infections
Recurrent pyogenic infections are associated with a deficiency in C5 to C8 components of the complement system.
Which of the following statements about the fermentation of sugars by Anthracoid bacilli is true?
1) Anthracoid bacilli ferment glucose, maltose, lactose, and sucrose, producing acid and gas.
2) Anthracoid bacilli do not ferment glucose but ferment maltose, lactose, and sucrose.
3) Anthracoid bacilli only ferment glucose.
4) Anthracoid bacilli ferment glucose, maltose, and lactose, but not sucrose.
Anthracoid bacilli ferment glucose, maltose, lactose, and sucrose, producing acid and gas.
What is the first X-linked immunodeficiency disease to have been recognized?
1) X-linked agammaglobulinemia
2) Severe combined immunodeficiency (SCID)
3) X-linked chronic granulomatous disease (CGD)
4) Wiskott-Aldrich syndrome
General Microbiology Answer: 1the first X-linked immunodeficiency disease to be recognized is X-linked agammaglobulinemia. It is a primary immunodeficiency disorder caused by a mutation in the X-chromosome-linked gene responsible for the production of antibodies (specifically, immunoglobulins), leading to a deficiency of B cells and impaired humoral immunity.