Expression of pertussis toxin subunit S4 as an intracytoplasmic protein in Bacillus subtilis (2023)

FAQs

What is the mechanism of action of pertussis toxin? ›

Pertussis toxin (PT) utilizes a retrograde transport pathway through the Golgi complex and endoplasmic reticulum (ER) to gain entry to the cell cytosol. ATP binding to PT B oligomer (PTB) in the ER promotes holotoxin dissociation for further transport of the active subunit.

Pertussis toxin (PTX) has been widely used as a reagent to characterize the involvement of heterotrimeric G-proteins in signalling. This toxin catalyses the ADP-ribosylation of specific G-protein alpha subunits of the Gi family, and this modification prevents the occurrence of the receptor-G-protein interaction.

Pertussis toxin (PT) is a protein-based AB₅-type exotoxin produced by the bacterium Bordetella pertussis, which causes whooping cough. PT is involved in the colonization of the respiratory tract and the establishment of infection.

Pertussis toxin (PT) is an AB-type protein toxin that consists of an enzymatic A moiety and a cell-binding B moiety (reviewed in (1, 2)). PT A (the S1 subunit) activates certain Gα proteins by an ADP-ribosylation reaction that utilizes NAD as a donor molecule.

DISEASE STATES AND VACCINES: SELECTED CASES

Part A is an enzymatically active subunit (S1) that has ADP ribosyltransferase activity on certain members of the G-protein family located on mammalian cells that are involved in transduction of receptor signals on cell membranes.

Pertussis Toxin Exploits Host Cell Signaling Pathways Induced by Meningitis-Causing E. coli K1-RS218 and Enhances Adherence of Monocytic THP-1 Cells to Human Cerebral Endothelial Cells.

Bordetella pertussis produces several toxins that affect host-pathogen interactions. Of these, the major toxins that contribute to pertussis infection and disease are pertussis toxin, adenylate cyclase toxin-hemolysin and tracheal cytotoxin.

Bordetella pertussis

pertussis is a fastidious, gram-negative bacterium requiring special media for isolation. B. pertussis produces multiple antigenic and biologically active products including: Pertussis toxin.

Pertussis toxin (PTX)-sensitive GTP-binding proteins (G proteins) are essential intermediaries subserving neuronal signal transduction pathways that regulate excitation-secretion coupling.

Acellular pertussis vaccine is combined with tetanus toxoid and diphtheria toxoid as DTaP (Infanrix and Daptacel) or Tdap (Boostrix and Adacel). DTaP and Tdap contain the same pertussis components, but Tdap contains a reduced quantity of some pertussis antigens and diphtheria toxoid.

How do you treat pertussis toxin? ›

Antibiotic treatment is available and important to prevent further transmission. However, antibiotics only reduce symptoms if administered in early stages, which rarely occurs due to a late diagnosis. Thus, no causative treatments against symptoms of whooping cough are currently available.

Clearly, PT is a key protective antigen in pertussis vaccines, despite the lack of a full understanding of its mechanism of action. PT is responsible for specific pertussis symptoms, but by itself does not recapitulate the full spectrum of disease.

Pertussis toxin is a member of the AB₅ family of toxins and is composed of five subunits (S1 to S5) present in a 1:1:1:2:1 ratio. Secretion is a complex process. Each subunit has a secretion signal that mediates transport to the periplasm, where processing and assembly occur.

There are three recognized stages of the disease: catarrhal, paroxysmal, and convalescent. The incubation period for Pertussis is 7 to 10 days.

Stimulation of GABA_B1a+2 receptors significantly increased current density, and this was sensitive to PTx.

Polymerase chain reaction (PCR) is an important tool for timely diagnosis of pertussis and is increasingly available to clinicians. PCR is a molecular technique used to detect DNA sequences of the Bordetella pertussis bacterium and unlike culture, does not require viable (live) bacteria present in the specimen.

It is a highly infectious bacterial disease involving the respiratory tract. It is caused by a bacterium (Bordetella pertussis or Bordetella parapertussis ) that is found in the mouth, nose and throat of an infected person.

Whooping cough, also known as pertussis, is a very contagious respiratory illness caused by a type of bacteria called Bordetella pertussis. The disease is only found in humans.

With time, the body's immune system develops antibodies which are specialised immune proteins that recognise that whooping cough bacteria are foreign. The antibodies stick to the bacteria and help the body's immune cells to respond to fight the infection.

Bordetella pertussis, the causative agent of whooping cough, is internalized by several cell types, including epithelial cells, monocytes, and neutrophils. Although its ability to survive intracellularly is still debated, it has been proven that cell-mediated immunity (CMI) plays a pivotal role in protection.

What is the pathway of B. pertussis? ›

B. pertussis is transmitted by aerosols and infects the ciliated epithelium of the airways. There is no further dissemination of the infection, but bacterial toxins produced in the respiratory tract contribute to local and systemic disease pathogenesis [10–13].

Some of these factors, including pertussis toxin (PT), adenylate cyclase, tracheal cytotoxin, dermonecrotic toxin, and lipopolysaccharide, exert a toxic effect. Other virulence factors, such as filamentous hemagglutinin (FHA), fimbriae, pertactin (Prn), and PT, have been reported to mediate the adherence of B.

Of the virulence factors produced by Bordetella organisms, only tracheal cytotoxin induces paralysis and destruction of respiratory ciliated epithelium, the hallmark of pertussis disease.

These toxins include the pertussis toxin (exotoxin) that activates host cell production of cAMP to modulate cell protein synthesis regulation, a tracheal cytotoxin that causes destruction of ciliated epithelial cells, and a cell surface hemagglutinin to assist in bacterial binding to the host cells.

By taking a nose and throat swab, they can test for the Bordetella pertussis bacteria in culture or a more rapid polymerase chain reaction test. Your doctor may suggest a blood test to check your white blood cell count, which, if low, signals the presence of an infection.

Gram-negative infections include those caused by Klebsiella, Acinetobacter, Pseudomonas aeruginosa, and E. coli., as well as many other less common bacteria.

Scientists consider culture the gold standard because it is the only 100% specific method for Bordetella pertussis identification. Other tests that can be performed include polymerase chain reaction (PCR) and serology.

With blood testing, pertussis IgG antibodies will be present in those who have been vaccinated or have had a past infection. IgM and IgA antibodies may indicate recent vaccination or infection and will only be present for a short period of time (2-3 months).

Bordetella pertussis is a small (approximately 0.8 μm by 0.4 μm), rod-shaped, coccoid, or ovoid Gram-negative bacterium that is encapsulated and does not produce spores.

Any adult 19 years of age or older who has never received a dose of Tdap should get one as soon as feasible. You should administer Tdap regardless of interval since the last tetanus or diphtheria toxoid-containing vaccine. This should be followed by either a Td or Tdap shot every 10 years.

Can you get pertussis if vaccinated? ›

Can people who have been vaccinated still get whooping cough? Sometimes when vaccinated people are exposed, they get whooping cough anyway, although they usually have milder symptoms, a shorter illness, and may be less likely to spread the disease to others.

DTaP and Tdap vaccine are safe and effective at preventing diphtheria, tetanus, and pertussis. Vaccines, like any medicine, can have side effects. The most common side effects are usually mild and go away on their own. Severe allergic reactions following vaccination are rare, but can be life threatening.

Pertussis bacteria die off naturally after three weeks of coughing. If antibiotics are not started within that time, they are no longer recommended. Antibiotics can also be given to close contacts of persons with pertussis to prevent or lessen the symptoms.

Pertussis bacteria are spread through droplets produced during coughing or sneezing. These droplets don't travel very far through the air and usually only infect persons nearby.

The best way to prevent whooping cough is to get vaccinated. Two vaccines in the United States help prevent whooping cough: DTaP and Tdap. These vaccines also provide protection against tetanus and diphtheria.

Pertussis toxin is an environmental hazard. Do not allow inactivated toxin to enter the drain. Solid waste including pipettes, containers, etc. that come in contact with toxin must be disinfected with 10% bleach prior to disposal in biohazard waste container.

Macrolides erythromycin, clarithromycin, and azithromycin* are preferred for the treatment of pertussis in persons 1 month of age and older. For persons 2 months of age and older, an alternative to macrolides is trimethoprim-sulfamethoxazole.

There are 2 vaccines that include protection against whooping cough: The DTaP vaccine protects young children from diphtheria, tetanus, and whooping cough. The Tdap vaccine protects preteens, teens, and adults from tetanus, diphtheria, and whooping cough.

Pertussis (Whooping Cough)

Killed (inactivated) vaccines are made from a protein or other small pieces taken from a virus or bacteria. The whooping cough (pertussis) vaccine is an example.

What is the difference between whooping cough and pertussis? ›

Pertussis is also called whooping cough. It is a serious lung infection caused by bacteria. It is also very contagious and causes coughing fits. Whooping cough is most serious for babies with very small airways.

Whooping cough is caused by a type of bacteria called Bordetella pertussis. It spreads from person to person. People who have pertussis usually spread it through coughing, sneezing, or breathing very close to someone. It can also sometimes be spread by touching an infected surface and then touching your nose or mouth.

People with pertussis are most infectious during the catarrhal period and during the first two weeks after onset of the cough (approximately 21 days).

Pertussis toxin (PT) is a protein-based AB₅-type exotoxin produced by the bacterium Bordetella pertussis, which causes whooping cough.

Diphtheria toxin kills cells by inhibiting eukaryotic protein synthesis, and its mechanism of action has been extensively characterized. This potent toxin inactivates elongation factor (EF-2) required for protein synthesis (Collier, 1967).

Bordetella pertussis produces extracytoplasmic adenylate cyclase toxin (AC toxin) which penetrates target cells and, upon activation by host calmodulin, generates high levels of intracellular cyclic AMP (cAMP). As a result, bactericidal functions of immune effector cells are impaired.

The diphtheria toxin enters and kills the cell through the combined action of its three domains: the catalytic domain (C-domain), the translocation domain (T-domain), and the receptor-binding domain (R-domain) [1].

Diphtheria toxin can be proteolytically cleaved into two fragments: an N-terminal fragment A (catalytic domain), and fragment B (transmembrane and receptor binding domains). Fragment A catalyzes the NAD⁺-dependent ADP-ribosylation of elongation factor 2, thereby inhibiting protein synthesis in eukaryotic cells.

Diphtheria bacteria spread from person to person, usually through respiratory droplets, like from coughing or sneezing. People can also get sick from touching infected open sores or ulcers. Those at increased risk of getting sick include: People in the same household.

How does diphtheria toxin inhibit translation? ›

Diphtheria toxin (DT) inhibits eukaryotic translation elongation factor 2 (eEF2) by ADP-ribosylation in a fashion that requires diphthamide, a modified histidine residue on eEF2.

Standard pertussis vaccine prepared from killed whole cell Bordetella pertussis organisms has been in widespread use since the early 1950s. It has been effective in reducing the incidence of pertussis in the United States to low levels.

Diphtheria is caught by coming into contact with droplets from the respiratory tract of an infected person—particularly spread by coughing or sneezing. If the disease is cutaneous, it can be spread by coming into contact with the wounds or lesions of an infected person.

Diphtheria is fatal in 5–10% of cases, but children under the age of five have a mortality rate of up to 20%. Treatment involves antibiotics to kill the bacteria (erythromycin or penicillin for 14 days) and administering of diphtheria antitoxin (DAT) to neutralize the effects of the toxin⁴–⁶.

Diphtheria (dif-THEER-e-uh) is a serious bacterial infection that usually affects the mucous membranes of the nose and throat.

pertussis infection induces innate immune cell (such as neutrophils and macrophages) activation, as well as IFN-γ-producing and IL-17-producing T cells. The Th-17 T cells are instrumental for sIgA production. The infection also results in resident memory T cells (γδ and CD4⁺ T cells).

Pertussis is primarily a toxin-mediated disease. The bacteria attach to the cilia of the respiratory epithelial cells, produce toxins that paralyze the cilia, and cause inflammation of the respiratory tract, which interferes with the clearing of pulmonary secretions.