The Importance of Microbiology
MicroBiome Vs Microbiota
- Microbiomes - functional collection of multiple microbes in a particular enviromental system. (Microbiota + "theater of activity"
- Microbiota - All types of microorganisms present in a microhabitat
BENEFITS
- Biomarkers - predicting diseases
- Designing targeted therapies
- Personalized drug therapies and probiotics
Metagenomics - Study of genetic material from enviromental/clinical samples
Using metagenomic sequencing or metasequencing techniques
major microbial populations in human body
- GI track (Gastrointestinal track) - Stomach, Small intestine, Large Intestine
phylotypes - group of organism by phenetic relationship
Human gut phylotypes :
- Gastric fluid : Firmicutes, Bacteroidetes and Actinobacteria
- Mucus Layer - Firmicutes and Proteobacteria
Stomach - Helicobacter pylori - in gastric mucosa
Large Intestine - Small Intestine goes to the ileum empties into the cecum.
- E. coli
microbial communities in the gastrointestinal track
enterotypes - stable clusters of communities co-existing
- 3 types - Bacteroides, Prevotella, Ruminococcus
Products of Metabolites
- Vitamin production
- Modification of steroids
- Amino acid biosynthesis
- Shotgun Metagenomic Sequencing
- 16S rRNA
Development
- Colonization begins - Birth - Source of vitamins and education for immune system
Disorders
- Inflammatory Bowel Disease (IBD) - Dysbiosis - disruption of homeostasis
Antibiotics - decrease microbes in the gut
C. difficile - spore-former, antibiotic-resistant opportunistic pathogen
Probiotics
Prebiotics - carbohydrates, provide nutrition for fermentative gut bacteria
Synbiotics - combines both pro and pre-biotics
Human Virome
- RNA virus Genomes - Typically smaller than DNA viruses, Single/double stranded
- Viroids - Naked infectious RNAs that cause plant diseases
The Baltimore Scheme
- 7 classes in relation to its mRNA
= 3 classes of DNA genome
= 4 classes of RNA genome
- Class 1 - double stranded (+/-) - RNA replicase makes (+) strand to be used as mRNA and template
- Class 2 - DNA (+) - produces replicative form
- Class 3 - RNA (+/-) - must carry RNA replicase
- Class 4 - RNA (-) - genome mRNA
- Class 5 - RNA (-) - RNA replicase makes (+) strand to be used as mRNA and template
- Class 6 - RNA (+)
- Class 7 - DNA (+/-) - Uses reverse transcriptase Hepatitis B (HBV)
Genetic Transfer Processes - Transduction and Lysogeny
Lysogeny - Viral genes replicated not transcribed
- Prophage - Lysogenic form of Viral DNA
Transduction: the transfer of host genes from one cell to another by a virus, 2 modes - generalized and specialized
- Generalized - donor genes not part of viral genome and cannot replicate independently, Transducing particle - Particles containing bacterial host DNA
Bacteriophages - protective role in human health, first line of defense against pathogens
Phage - symbiotic relationship
Microbiology of Water
Sources
- Potable Water - Used for drinking and cooking
= Filtration and Chlorination
- Recreational Water - Public ponds, lakes, Swimming pool
Testing
- Indicator organism - signals potential for diseases
Microbiology of Food |
