Microbial forensic by Debmalya Biswas.pptx

Microbial forensic

1. WELCOME

2. MICROBIAL FORENSIC Unraveling Mysteries with Microbes

3. INTRODUCTION Definition of microbial forensics: Microbial forensics involves the use of microbiology in legal investigations to solve crimes, address bioterrorism threats, and identify the sources of disease outbreaks. - Importance: Microbial forensics plays a critical role in safeguarding public health, ensuring justice, and enhancing national security. - Brief history and development: Microbial forensics has evolved rapidly with advancements in microbiological techniques and genetic analysis, becoming an indispensable tool in forensic science.

4. MICROBIAL SIGNATURES - Explanation: Microbes possess unique genetic and phenotypic characteristics that can act as signatures, aiding in their identification and tracing. - Genetic and phenotypic markers: Various genetic markers, such as DNA sequences and fingerprinting techniques, are used alongside phenotypic traits for microbial identification.

5. In 2009, Sierra Bouzigard was found murdered in Moss Bluff, Louisiana, but the case quickly went cold because the DNA evidence didn’t match anyone in the database. Then in 2015, using a relatively new technology called DNA phenotyping, the DNA evidence was used to simulate what the killer would probably have looked like. Soon after, the sketch of a white male was recognized, and the killer was brought to justice. Case studies Applications in Crime Investigations: In 1981, 24-year-old Nova Welsh was strangled to death in Birmingham, England. Her body was found three weeks later, stuffed inside a cupboard that was sealed shut with a piece of chewing gum. The crime went unsolved for nearly 36 years when DNA extracted from the chewing gum was found to match that of Nova’s former boyfriend, Osmond Bell. He claimed he’d used the gum quite innocently—a simple home repair unrelated to Nova’s death. But the DNA also matched that on an envelope containing an anonymous letter pointing the finger at someone else for the murder (which is, itself, a known forensic counter-measure).

6. There are some advantages to utilize microorganism or their toxins as weapon to commit crime. This include, ability to proliferate pathogens (by culture), easy to access and reasonably low cost to originate pathogens.The more sophisticated techniques and expertise is requires because of the prospective of an attack, forensic science need to be develop to aid in the investigation. BIOTERRORISM

7. Historical Background Case study 1 In 1347 plague or Black Death struck Europe with brutal force. By 1351, only four years later, the plague had killed 1/3 of the population (about 25 million people). Over the next 80 years, the disease struck again and again, eventually wiping out 75% of the European population. Some historians believe that this disaster changed European culture and prepared the way for the Renaissance. The 2001 anthrax attacks, also known as Amerithrax from its FBI case name, occurred within the United States over the course of several weeks beginning on September 18, 2001, one week after the September 11 attacks. Letters were mailed containing anthrax spores to several news media offices and to Democratic Senators Tom Daschle and Patrick Leahy, killing 5 people and infecting 17 others. There are numerous documented example of the use of pathogens in major conflicts or terrorism over the course of history.Microbial diseases undoubtedly played a major role in historical events such as the decline of the Roman Empire and the conquest of the New World. Case study 2

8. Bioterrorism Threat Detection DELFIA system The BV M-series device Quantititive real tome PCR (dissociation-enhanced lanthanide fluorescence immunoassay) is an example of the format based on time-resolved fluorescence. It uses electrochemiluminescence to detect reporter molecules used in the sandwich assay. In BV assays, paramagnetic beads are used as carriers of the antibodies. combines PCR amplification with simultaneous detection of amplification products, based on changes in fluorescence intensity, proportional to the increase of the product.

9. OUTBREAK INVESTIGATION The first step in case of suspected bio crime or bio terrorism is the collecting of evidences at the crime scene. The first responder to any suspected bio attempt should first understand the biological nature of the microorganisms and the safety of own self. The next major step is to associate the source of causative agent with specific individual of groups. Molecular variation can reveal about the type of microorganism involved and these molecular signature encountered more useful 16s r DNA technology is much more developed now and it is easier to screen expression libraries and patterns. It reveals the population structure, species evaluation. DNA analysis can also discriminate the different bacterial profiles between individual in a way that has forensic value. Hyphenated technologies like MALDI-TOF, GC-MS especially when coupled with mass spectrometry, is the analytical method of choice for identification of biomarker compounds present in organic mixtures extracted from geological, environmental,and biological samples. LC-MS are becoming well known for detection of differences in protein and small molecules. These techniques can be applied directly to untreated cellular fractions or cellular suspension to produce chemotaxonomic signature profile, analysis of bacterial RNA and DNA and rapid characterization of bacteria at the genus, species and strain level. Efforts have been shown that ultrafine differences between closely related strains can be clearly delineated using MALDI-TOF.

10. Challenges o Storage Time of collection Depth of sequencing Limited biomass Privacy of subject Temporal variability

11. THANK YOU Credit | Image: Unsplash