Microbiology sheet (1&2)

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1 Microbiology sheet (1&2) LECTURER: intro to microbiology CORRECTED BY : Tamara Shawabkah & Mohammad Jomaa DATE: 18/9 + 22/9

2 Region in the body that don t have microorganisms: 1) Blood 2) CSF 3) Upper part of stomach Why Study Microbes? 1. Microbes and Man in Sickness and Health Parasitism; Pathogens (disease causing) Infectious disease is leading cause of death in developing countries (45%). Commensalisms; Natural Microbiota (do no harm) Example :E.coli which is have rule in 1)absorption of vitamin K 2)digestion of un digested food 3)barrier of infection (by control the ph) Mutualisms; Natural Microbiota (do us good) 2. Major Modern Applications (Biotechnology): Recombinant DNA technology; cloning Industrial Applications (antibiotics; chemical production via fermentation) Sewage treatment to decompose organic matter Bioremediation of toxic waste 3. The Role of Microbes in Ecosystems Sources for drug discovery (antibiotics & antiviral drugs) Cycling of Elements (ecosystem management; global climate change) Agriculture (crop diseases; nutrient enhancement) Biotechnology & Bioremediation Biotechnology- when humans manipulate (micro)organisms to make products in an industrial setting Genetic engineering- create new products and genetically modified organisms (GMOs) Recombinant DNA technology- technology used to engineer GMOs capable of synthesizing desirable proteins (i.e. medicines, hormones, and enzymes) Bioremediation - activity of microbes in the environment helping to restore stability or clean up toxic pollutants Oil spills Chemical spills Water and sewage treatment

The microbial world is made up of microorganisms and viruses. Microbiology is the branch of biological sciences concerned with the study of these microbes.

3 The microbial world is made up of microorganisms and viruses. Microbiology is the branch of biological sciences concerned with the study of these microbes. Microorganisms are unicellular organisms (capable of existence as single cells), too small to be seen with the naked eye. Among all forms of life on the earth, microorganisms predominate in numbers of species and in biomass, but their occurrence is generally under appreciated because of their small size and the need for a microscope to see individual cells. Although a light microscope is generally required to visualize a single microbial cell, microbial colonies and communities can readily be observed in nature. Viruses are noncellular entities and cannot be considered microorganisms. Viruses and cellular microorganisms are considered microbes. The term organism is a descriptive term that implies cellular life. Hence, microorganisms are a type of cellular life that is microscopic in size. Viruses are not considered microorganisms because they are not cells. Viruses consist of nucleic acid (DNA or RNA) enclosed in a protein coat. They lack many essential properties of cells, including membranes, ribosomes and metabolic enzymes. Viruses are considered microbes, but not microorganisms, and hence are not "alive". Which are the microorganisms? Life forms, or other self replicating entity, that requires microscopy technology to be clearly visualized. All prokaryotic and many eukaryotic life forms. Many are unicellular, sometimes cells are organized in filaments or clumps, and others are complex with only a portion of their life cycle being microscopic. Most can carry out life processes independently from other cells, others are highly parasitic. They often require specialized techniques for their study: microscopy, culturing, biochemical and molecular.

4 Slide 6 We have two domain 1) prokaryotic 2) eukaryotic This is major domain fold the organism Difference between prokaryotic and eukaryotic **Eukaryotic >>true nucleus, nucleus membrane, cytoplasmic organelles (Golgi apparatus mitochondria ) **prokaryotic>> means that is primitive >>there is no nucleus, nuclear material distributed in one part of the cytoplasm In fact the prokaryotic cell nucleus called nucleoid Nucleoid: it is the region where the chromosomes locate Note: ribosomes present in both (eukaryotic and prokaryotic) but there is deferent between them In prokaryotic ribosome called 70s In eukaryotic ribosomes called 80s : S تعني عامل الترسية coefficient( )sedimentation ويتم حساب كميتها تجهاز الطرد المركسي Each ribosomes contain 2 subunit: large subunit and small subunit Eukaryotic prokaryotic Large subunit 50s 50s Small subunit 40s 30s

5 **The Eukaryotic cell would be about 50x bigger than the prokaryotic cell Slide 7 minute: 8 Eukaryotic Cell Prokaryotic Cell Nucleus Present Number of chromosomes More than one Usually multicellular Absent One--but not true chromosome: Plasmids Usually unicellular (some cyanobacteria may be In prokaryotic cell >>the cell have DNA in the cytoplasm and they have extra chromosomes Extra chromosomes: is an DNA but it is independent from the normal cell DNA and it is replication too These extra chromosomes called plasmide The gene that s located on plasmid it s not necessary for the growth of bacteria..while the shape and metabolism is determined by normal chromosomes which is basic for bacteria cell مثال : شخص لون عيونه زرقاء واخر سوداء..هنا ال يمكن ان تتغير لون العيون من االزرق لالسود او العكس وكذلك البكتيريا ال يمكن ان يتغير شكلها بعد فترة..الن هذه الصفات Carried on the gene on the chromosome (normal chromosome) What is the characteristic determined by plasmide??

6 The trait that are not essential for the growth of bacteria for example >>antibiotics resistant; enzyme production; toxins transfer Why?? Bactria are sensitive to x antibiotics. After period of time the bacteria resistant to x antibiotic.why?? Because gene that code of resistance of antibiotics could o plasmide (jumping gene) Bacteria can gain gene on plasmide and can eliminate it and can transport it to another bacteria and it is important in clinical medicine to treat patients plasmide وبالتالي ممكن ان تنتقل من بكتيريا الخرى هذا يعني ان صفة المقاومة والحساسية محمولة على Genes transfer from one bacteria to one another by 1)conjugation (most popular) 2)transduction Archea is an old bacteria that s live in extreme environment such as (high and low ph, high osmotic pressure, high and low temperature) Eukaryotic cell >> all organisms in the world expect 1)bacteria 2)Archea 3)green blue Algi Cell Type Usually multicellular Usually unicellular (some cyanobacteria may be multicellular) True Membrane bound Nucleus Present Genetic Recombination Example Animals and Plants Microtubules Present Meiosis and fusion of gametes Absent Bacteria and Archaea Partial, undirectional transfers DNA Absent or rare There is no bacteria with constant characteristic for its life (always change)

Nucleus Present Absent Minute: 19 Number of chromosomes More than one Usually multicellular Cell Type True Membrane bound Nucleus Present Example Animals and Plants One--but not true chromosome:

7 Nucleus Present Absent Minute: 19 Number of chromosomes More than one Usually multicellular Cell Type True Membrane bound Nucleus Present Example Animals and Plants One--but not true chromosome: Plasmids Usually unicellular (some cyanobacteria may be multicellular) Absent Bacteria and Archaea Genetic Recombination Meiosis and fusion of gametes Partial, undirectional transfers DNA Microtubules Present Endoplasmic reticulum Present Mitochondria Present Cytoskeleton Present DNA wrapping on proteins. histone is a basic protein Eukaryotes wrap their DNA around proteins called histones. Absent or rare Absent Absent May be absent Multiple proteins act together to fold and condense prokaryotic DNA. No histones Ribosomes Larger Vesicles Present Golgi apparatus Present Chloroplasts smaller Present Absent Present (in plants) Absent; chlorophyll scattered in the cytoplasm Microscopic in Submicroscopic in size, composed of In prokaryotic cell there is some bacteria do photosynthesis so that it has chlorophyll separated in cytoplasm not in chloroplast Flagella Microscopic in size; membrane bound; usually arranged as nine doublets surrounding two singlets Permeability of Nuclear Selective Submicroscopic in size, composed of only one fiber not present Flagella is use to move

8 Note : flagella don t have any association or related to the cell speed in motion Note :there is no relation ship between number of flagella and active motion Flagella determine only if there is motile or no **bacteria can change its shape in respond to several factors such as : 1)enviroment 2)radiation Permeability of Nuclear Membrane Plasma membrane with steroid singlets Selective Yes Only in plant not present Usually no Usually chemically complexed cells and fungi in procaryoti cell there is some bactreia have steriod for example>>myoplasma hominis one of the smallest bacteria don t have cell wall..but it have plasma membrane with steroid (3 lyers of steroid).(normal bacteria cell have cell wall and plsma membrane without steroid) steroid it is a fatty lyer have rule and affect many things like motile and stabilty to the cell and many other things. steroid Cell wall Vacuoles Present Only in plant cells and fungi (chemically simpler) Usually chemically complexed Present In prokaryotic cell >> the cell wall is very important part of the bacteria because it is use in determing the type of gram stan (+ or -) This part is very important in clinical medicine in diagnosis

9 By using gram stain >>(gram - =red // gram + =purple) If we use lysosome or pencillin or others enzyme we can change the structure of cell wall and change it. Cell wall in prokaryotic cell called peptidoglycan or mural Minute :28 Cell size In prokyrotic cell >> myoplasma hominis it is very small and don t have cell wall but it has nuclear material in cytoplasm and have plasmic membrain which have steroide that supply and give stability to the cell Slide 9 Biologists recognize the existence of two fundamentally different types of cells in the microbial world, called procaryotic and eucaryotic cells. 1. Eucaryotic cells have a "true" nucleus (the region of the cell that contains genetic information or DNA) that enclosed in a nuclear membrane 2. Prokaryotic cells are said to have a "primitive" nucleus because their DNA is not enclosed within a nuclear membrane. The nuclear region of a prokaryotic cell is sometimes referred to as a nucleoid, but never as a nucleus.

10 Procaryotic and Eucaryotic cells Eucaryotic cells are always bounded by a membrane, just as prokaryotic cells are. Some eucaryotic cells are also surrounded by a cell wall, but eucaryotic cells do not have capsules. Mitochondria are present in nearly all eucaryotic cells and produce the cell's energy by breaking down food. Chloroplasts, in contrast, are present only in plants and algae and are used in photosynthesis, the process through which the organism uses energy from the sun to build sugars. Taxonomy of Life: The classification, or grouping, of organisms based on common characters used to reflect their evolutionary relatedness. Types of groups, taxa, are arranged in a hierarchy from the most general (Domain) to most specific. 3 Domains based on molecular analysis of ribosomal RNA. (Carl Woese 1980s) Two prokaryote domains: Bacteria and Archaea A single Eukaryote domain. Many Phyla within each domain.

11 Divided to 3 domains and each domains have several groups Domain : Eukaryotic Bacteria prokaryotic Archae prokaryotic Usually bacteria in lab live in normal temperature 37 (middle temperature) Every line represents a period of time and note the eukaryotic and archea are closed to each other but prokaryotic its far away Difference in taxonomy between us and them Humans Domain: Eukarya Kingdom: Animalia Phylum: Chordata Class: Mammalia Order: Primata Family: Hominidae Group: Homo Species: sapiens Intestinal Bacterium Domain: Bacteria (no kingdom) Phylum: Proteobacteria Class: γ-proteobacteria Order: Enterobacteriales Family: Enterobacteriaceae Genus: Escherichia Species: coli

12 The underline suffix ales mean order and the suffix aceae mean family Minute :34 Binomial nomenclature: (1+2) 1)Genus 2)species (must be italic or underlined) Genus name must begin in capital letter Example : E.coli O157:H7 >>(it is subspecies) O mean >> one of somatic antigen and the number 157 it is one type of several type begin to numbering from 1 H mean >>flagella antigen and the number is type of several type **bacteria may be capsulated or not capsulated (capsulated one is more dangerous to us than non-capsulated one) One of the capsule functions is being anti-phagocytic and allows the bacteria to proliferation and distribute in your body Minute :42

13 Bacteria is more common than Fungi Deffernt in ways of motile Amoeba>> Pseudopodia Ciliate >>cilia Flagellate >>flagella Viruses: An infectious particle with an acellular organization of protein and nucleic acids (RNA or DNA), and lacking independent metabolism. It requires the metabolism of a host cell in order to replicate. Viruses are about 50 to 200 nm in size.

14 Viruses can t survive without living with another cell Viruses that s surrounded by envelpe called enveloped viruse Compound microscope = bright filed microscope =student microscope Elctron microscope 600,000x Compound microscope 1000x Prion: An infectious aberrant brain protein that causes abnormal aggregation of similar normal brain proteins; no nucleic acids. Causes dementia and madness. Viruse contain only one DNA or RNA and not both with protien Prion conain only protien Virone contane only RNA and protien

Introductory Microbiology Dr. Hala Al Daghistani

Introductory Microbiology Dr. Hala Al Daghistani Why Study Microbes? Microbiology is the branch of biological sciences concerned with the study of the microbes. 1. Microbes and Man in Sickness and Health