Martha Clokie | |
---|---|
Born | Martha Rebecca Jane Clokie |
Alma mater | University of Dundee (BSc) University of Edinburgh (MSc) University of Leicester (PhD) |
Scientific career | |
Fields | Microbiology |
Institutions | University of Leicester Scripps Institution of Oceanography University of Warwick |
Thesis | Molecular studies of Southern Hemisphere disjunction in three plant genera, Eucryphia, Griselinia and Coriaria (2001) |
Website | www2 |
Martha Rebecca Jane Clokie is a professor of microbiology at the University of Leicester. [1] Her research investigates the identification and development of bacteriophages that kill pathogens in an effort to develop new antimicrobials. [2]
Clokie studied biology at the University of Dundee. [3] She graduated in 1996 and moved to Edinburgh, where she started a postgraduate degree in biodiversity. [3] She earned a master's degree at the University of Edinburgh in 1997 and moved to Leicester. Clokie earned her doctoral degree in molecular ecology at the University of Leicester in 2001 [4] for research on the evolution of three genera of plants: Eucryphia , Griselinia and Coriaria . [3]
After her PhD, Clokie was a postdoctoral researcher at the University of Warwick and the Scripps Institution of Oceanography. [3] Clokie started her research career investigating the molecular evolution of plants. [5]
Clokie joined the University of Leicester as a lecturer in 2007 and was promoted to Professor in 2016. [3] [1] She is interested in viruses known as bacteriophages which can be used to treat disease. Her work involves cyanobacteria and the sequencing of various bacteriophages. [6] She demonstrated that marine phages contain the genes responsible for photosynthesis, and that phages do not only exert pressure on the infection-survival mechanism of cyanobacteria but can acquire the genes of a bacteria's prey. [5]
Her research includes identifying specific phage combinations that can be used to destroy Clostridioides difficile Infections (CDI) while maintaining a healthy gut. [7] [8] CDI causes almost two fifths of diarrhoea associated with antibiotics in the Western world, and one in ten of patients die due to a lack of effective treatment. [7] [9] The bacteriophage could reduce the growth of C. difficile and simultaneously defend beneficial bacterial that are typically destroyed by antibiotics. [7] The bacteriophages can be delivered orally and result in destruction of C. difficile within two days. [7] [10] Clokie went on to demonstrate that C. difficile can evolve into a new species, with a specific strand that is adapted to spread quickly in hospitals. [11] The new species survives on the sugar-rich diets of Westerners and can evade common disinfectants. [11]
She has also worked on bacteriophages that can be used to prevent bacterial infections in Antheraea assamensis (Muga silkworms). [12] Muga silk is produced in Assam and is one of the most valuable silks in the world. They are at risk from Flacherie, a bacterial disease that is caused by larvae eating infected leaves. [12] Alongside working on silk worms, Clokie has explored the use of phages in the treatment of drug resistant urinary tract infections. She has shown that bacteriophages could be used to treat bacterial disease in pigs. [13] [14] These phages disable the Salmonella bacterial disease that infects pigs and can be added to pig feed. [14]
Clokie maintained bacteriophages were helping growing numbers of patients in compassionate use cases and could become routine for conditions like chronic UTIs and diabetic foot ulcers. Clokie stated “The risk from antibiotic resistance is dire and getting worse … I find it really shocking. Unless we have clinical trials, phages won’t become mainstream as a medicine, and that’s where we’re aiming.(...) I get fairly regular emails from doctors and patients wanting phages. Doctors have gone from being completely disinterested to ‘give me the phages now’ (…) There are people who need phages now because they’re dying.” [15]
Her publications include;
Clokie is founding editor-in-chief of the journal PHAGE: Therapy, Applications and Research. [20]
Clokie was awarded a Grand Challenges exploration fund award from the Bill & Melinda Gates Foundation. [21] This allowed her to investigate bacteriophages that could be used to eradicate Shigellosis. [21] In 2019 Clokie was interviewed on the BBC Radio 4 programme The Life Scientific . [22]
An antibiotic is a type of antimicrobial substance active against bacteria. It is the most important type of antibacterial agent for fighting bacterial infections, and antibiotic medications are widely used in the treatment and prevention of such infections. They may either kill or inhibit the growth of bacteria. A limited number of antibiotics also possess antiprotozoal activity. Antibiotics are not effective against viruses such as the ones which cause the common cold or influenza. Drugs which inhibit growth of viruses are termed antiviral drugs or antivirals. Antibiotics are also not effective against fungi. Drugs which inhibit growth of fungi are called antifungal drugs.
A bacteriophage, also known informally as a phage, is a virus that infects and replicates within bacteria and archaea. The term was derived from "bacteria" and the Greek φαγεῖν, meaning "to devour". Bacteriophages are composed of proteins that encapsulate a DNA or RNA genome, and may have structures that are either simple or elaborate. Their genomes may encode as few as four genes and as many as hundreds of genes. Phages replicate within the bacterium following the injection of their genome into its cytoplasm.
Salvador Edward Luria was an Italian microbiologist, later a naturalized U.S. citizen. He won the Nobel Prize in Physiology or Medicine in 1969, with Max Delbrück and Alfred Hershey, for their discoveries on the replication mechanism and the genetic structure of viruses. Salvador Luria also showed that bacterial resistance to viruses (phages) is genetically inherited.
A prophage is a bacteriophage genome that is integrated into the circular bacterial chromosome or exists as an extrachromosomal plasmid within the bacterial cell. Integration of prophages into the bacterial host is the characteristic step of the lysogenic cycle of temperate phages. Prophages remain latent in the genome through multiple cell divisions until activation by an external factor, such as UV light, leading to production of new phage particles that will lyse the cell and spread. As ubiquitous mobile genetic elements, prophages play important roles in bacterial genetics and evolution, such as in the acquisition of virulence factors.
Phage therapy, viral phage therapy, or phagotherapy is the therapeutic use of bacteriophages for the treatment of pathogenic bacterial infections. This therapeutic approach emerged at the beginning of the 20th century but was progressively replaced by the use of antibiotics in most parts of the world after the Second World War. Bacteriophages, known as phages, are a form of virus that attach to bacterial cells and inject their genome into the cell. The bacteria's production of the viral genome interferes with its ability to function, halting the bacterial infection. The bacterial cell causing the infection is unable to reproduce and instead produces additional phages. Phages are very selective in the strains of bacteria they are effective against.
Transduction is the process by which foreign DNA is introduced into a cell by a virus or viral vector. An example is the viral transfer of DNA from one bacterium to another and hence an example of horizontal gene transfer. Transduction does not require physical contact between the cell donating the DNA and the cell receiving the DNA, and it is DNase resistant. Transduction is a common tool used by molecular biologists to stably introduce a foreign gene into a host cell's genome.
Lysogeny, or the lysogenic cycle, is one of two cycles of viral reproduction. Lysogeny is characterized by integration of the bacteriophage nucleic acid into the host bacterium's genome or formation of a circular replicon in the bacterial cytoplasm. In this condition the bacterium continues to live and reproduce normally, while the bacteriophage lies in a dormant state in the host cell. The genetic material of the bacteriophage, called a prophage, can be transmitted to daughter cells at each subsequent cell division, and later events can release it, causing proliferation of new phages via the lytic cycle.
Fecal microbiota transplant (FMT), also known as a stool transplant, is the process of transferring fecal bacteria and other microbes from a healthy individual into another individual. FMT is an effective treatment for Clostridioides difficile infection (CDI). For recurrent CDI, FMT is more effective than vancomycin alone, and may improve the outcome after the first index infection.
Bacteriophage (phage) are viruses of bacteria and arguably are the most numerous "organisms" on Earth. The history of phage study is captured, in part, in the books published on the topic. This is a list of over 100 monographs on or related to phages.
Cyanophages are viruses that infect cyanobacteria, also known as Cyanophyta or blue-green algae. Cyanobacteria are a phylum of bacteria that obtain their energy through the process of photosynthesis. Although cyanobacteria metabolize photoautotrophically like eukaryotic plants, they have prokaryotic cell structure. Cyanophages can be found in both freshwater and marine environments. Marine and freshwater cyanophages have icosahedral heads, which contain double-stranded DNA, attached to a tail by connector proteins. The size of the head and tail vary among species of cyanophages. Cyanophages infect a wide range of cyanobacteria and are key regulators of the cyanobacterial populations in aquatic environments, and may aid in the prevention of cyanobacterial blooms in freshwater and marine ecosystems. These blooms can pose a danger to humans and other animals, particularly in eutrophic freshwater lakes. Infection by these viruses is highly prevalent in cells belonging to Synechococcus spp. in marine environments, where up to 5% of cells belonging to marine cyanobacterial cells have been reported to contain mature phage particles.
A corynebacteriophage is a DNA-containing bacteriophage specific for bacteria of genus Corynebacterium as its host. Corynebacterium diphtheriae virus strain Corynebacterium diphtheriae phage introduces toxigenicity into strains of Corynebacterium diphtheriae as it encodes diphtheria toxin, it has subtypes beta c and beta vir. According to proposed taxonomic classification, corynephages β and ω are unclassified members of the genus Lambdavirus, family Siphoviridae.
Autographiviridae is a family of viruses in the order Caudovirales. Bacteria serve as natural hosts. There are 373 species in this family, assigned to 9 subfamilies and 133 genera.
In biology, a pathogen, in the oldest and broadest sense, is any organism or agent that can produce disease. A pathogen may also be referred to as an infectious agent, or simply a germ.
Enzybiotics are an experimental antibacterial therapy. The term is derived from a combination of the words “enzyme” and “antibiotics.” Enzymes have been extensively utilized for their antibacterial and antimicrobial properties. Proteolytic enzymes called endolysins have demonstrated particular effectiveness in combating a range of bacteria and are the basis for enzybiotic research. Endolysins are derived from bacteriophages and are highly efficient at lysing bacterial cells. Enzybiotics are being researched largely to address the issue of antibiotic resistance, which has allowed for the proliferation of drug-resistant pathogens posing great risk to animal and human health across the globe.
Clostridioides difficile is a bacterium known for causing serious diarrheal infections, and may also cause colon cancer. It is known also as C. difficile, or C. diff, and is a Gram-positive species of spore-forming bacteria. Clostridioides spp. are anaerobic, motile bacteria, ubiquitous in nature and especially prevalent in soil. Its vegetative cells are rod-shaped, pleomorphic, and occur in pairs or short chains. Under the microscope, they appear as long, irregular cells with a bulge at their terminal ends. Under Gram staining, C. difficile cells are Gram-positive and show optimum growth on blood agar at human body temperatures in the absence of oxygen. C. difficile is catalase- and superoxide dismutase-negative, and produces up to three types of toxins: enterotoxin A, cytotoxin B and Clostridioides difficile transferase. Under stress conditions, the bacteria produce spores that are able to tolerate extreme conditions that the active bacteria cannot tolerate.
The Center for Innovative Phage Applications and Therapeutics (IPATH) is the first phage therapy center in North America, founded in the UC San Diego School of Medicine in June 2018, with seed funding from UC San Diego Chancellor Pradeep Khosla. The center was founded by Steffanie A. Strathdee and Robert "Chip" Schooley, both professors at UC San Diego School of Medicine. The center currently treats patients with life-threatening multi-drug resistant infections with phage therapy, on a case-by-case basis, through the Food and Drug Administration's (FDA's) compassionate use program. IPATH aims to initiate phase I/II phage therapy clinical trials, focusing on patients with cystic fibrosis and infections related to implantable hardware, such as pacemakers and prosthetic joints. The first planned clinical trial is set to look at otherwise healthy cystic fibrosis patients that are shedding Pseudomonas aeruginosa.
Benjamin K. Chan is a research scientist at Yale University in the department of Ecology and Evolutionary Biology. He was born in 1980 to a U.S. Asian father, an engineer, and an American mother. He is known for his work in phage therapy exploiting genetic trade-offs to treat antibiotic resistant bacterial infections. He currently lives in Guilford, Connecticut.
Robert "Chip" T. Schooley is an American infectious disease physician, who is the Vice Chair of Academic Affairs, Senior Director of International Initiatives, and Co-Director at the Center for Innovative Phage Applications and Therapeutics (IPATH), at the University of California San Diego School of Medicine. He is an expert in HIV and hepatitis C (HCV) infection and treatment, and in 2016, was the first physician to treat a patient in the United States with intravenous bacteriophage therapy for a systemic bacterial infection.
Multidrug-resistant bacteria are bacteria that are resistant to three or more classes of antimicrobial drugs. MDR bacteria have seen an increase in prevalence in recent years and pose serious risks to public health. MDR bacteria can be broken into 3 main categories: Gram-positive, Gram-negative, and other (acid-stain). These bacteria employ various adaptations to avoid or mitigate the damage done by antimicrobials. With increased access to modern medicine there has been a sharp increase in the amount of antibiotics consumed. Given the abundant use of antibiotics there has been a considerable increase in the evolution of antimicrobial resistance factors, now outpacing the development of new antibiotics.
Vincent A. Fischetti is an American microbiologist and immunologist, and Head of the Laboratory of Bacterial Pathogenesis and Immunology at Rockefeller University in New York City.
{{cite web}}
: CS1 maint: numeric names: authors list (link){{cite web}}
: CS1 maint: numeric names: authors list (link){{cite web}}
: CS1 maint: numeric names: authors list (link){{cite web}}
: CS1 maint: numeric names: authors list (link){{cite web}}
: CS1 maint: numeric names: authors list (link)