Introduction To Microbiology PDF

Microbiology: science studies the microbes,s life (micro = minute (small) + bio = alive (life) + logia = study) including Applied Microbiology and Pure Microbiology. Microbe: minute organism invisible by naked eyes as (bacteria- archaea -fungi-algae-virus-protozoa). Branches of Applied Microbi...

Microbiology: science studies the microbes,s life (micro = minute (small) + bio = alive (life) + logia = study) including Applied Microbiology and Pure Microbiology. Microbe: minute organism invisible by naked eyes as (bacteria- archaea -fungi-algae-virus-protozoa). Branches of Applied Microbiology include : Medical Microbiology – Veterinary Microbiology - Food Microbiology - Water microbiology (or Aquatic Microbiology)- ………………………………etc.. Branches of Pure Microbiology include: 1-Bacteriology: Science studies bacteria including: a- General Bacteriology: Science studies the biology of bacteria. b- Systematic Bacteriology: Science studies the classification of bacteria, properties and interrelationships between bacteria (the diversity and genetic relationship). 2- Mycology: Science studies the fungi. 3- Phycology: Science studies the Algae. 4- Virology: Science studies the viruses. 5- Immunology: Science studies immunity. 6-Microbial physiology: Science studies cell structure of microbes, microbial metabolism and microbial growth. 7-Microbial ecology: Science studies the relationship between microbes and their environment 8- Microbial genetics: Science studies microbes,s genetics ( the genes and their functions). Why are we studying Microbiology? 1- Maintaining the human health. 2- Industrial role as Microbiology play important role in many industries as (bread, cheese,………. , and Biotechnology). * Biotechnology is using of microorganism cell or cell components to make products (commercial production of food, antibiotics, vaccine, or….etc. 3- Nature balance (decomposition of dead and organic matters, role in carbon and nitrogen cycles). 4- Environmental role (bioremediation as heavy metal chelation). 5- Improving animal (fish) production. As (probiotics,……………etc.  Taxonomy of microbes -The living organisms recently were divided into five kingdoms based on their cell anatomy and the energy yielding systems which are: 1- Animals kingdom 2- Plants kingdom 3- Fungi kingdom 4- Protista kingdom (unicellular living organism (Eukaryotes) not plant or Animal or fungi) as algae (plant–like) and Protozoa (animal-like) 5- Monera kingdom (Bacteria) -The living organisms were divided according to the cell anatomy to: 1- Prokaryotes (Before nucleus): includes bacteria and blue green algae(cyanobacteria) which characterized by (no nuclear membrane and no nucleolus). 2- Eukaryotes (true nucleus): includes fungi, protozoa, plants, animals and algae and characterized by (presence of nuclear membrane and nucleolus).  Unicellular and Prokaryotes cell size is smaller than the cell size of Eukaryotic.  No nuclear membrane and no nucleolus.  Genetic material present Free in the cytoplasm.  Genetic material includes (chromosome = nucleoid – Plasmid – Transposons).  Chromosome is single circular double stranded supercoiled DNA and Histones absent (histones are proteins present in Eukaryotic nucleus to condense DNA).  Prokaryotes generally have only one allele for a particular gene (have haploid genes). *A gene is the functional unit of the nucleoid or plasmid, which is a liner sequence nucleotide. Alleles are different versions (copies) of the same gene.  Operons are prokaryotic character where more than one gene are expressed in groups on the same RNA piece.  Transcription and translation occur in the cytoplasm (same place).  There are not endoplasmic reticulum or mitochondria or Golgi Body (Membrane-bound organelles).  Prokaryotes ribosomes are smaller than Eukaryotic ribosomes(70S).  Respiration (Respiratory enzymes) bound to the plasma membrane.  Cell wall present and usually peptidoglycan (not Archaea) is the main component.  There are variety of inclusions bodies associated with nutrient storage.  In prokaryotes, cell division by binary fission.  Unicellular or multicellular organisms.  There are nuclear membrane and nucleolus.  Genetic material present in nucleus.  Genetic material includes (chromosomes – Plasmid may present).  Chromosomes are Multiple linear chromosomes, histone proteins are present.  Eukaryotes have diploid genes (two gene copies one from the mother and one from the father).  Introns are Eukaryotic character which are non-coding sequence or non-expressed sequence.  Transcription occurs in the nucleus and translation occurs in the cytoplasm (different places).  There are endoplasmic reticulum, mitochondria and Golgi Body (Membrane-bound organelles).  Eukaryotic ribosomes are larger than Prokaryotes ribosomes(80S).  Respiration (Respiratory enzymes) in The Mitochondria.  Cell wall if presents it is formed of cellulose or chitin. Fig. (1): Eukaryoteic and Prokaryotic cells.  Cell division by mitosis and meiosis.