Presentation on theme: " Psychrophiles, cells that grow best at low temperatures below 20oC Mesophiles have temperature optima in the range of 20 to 50oC Thermophiles grow."— Presentation transcript:
Psychrophiles, cells that grow best at low temperatures below 20oC Mesophiles have temperature optima in the range of 20 to 50oC Thermophiles grow best at temperatures greater than 50oC.
Aerobic microorganisms require O2 for growth and metabolism. Anaerobic microorganisms are inhibited by the presence of O2 Facultative organisms can switch the metabolic pathways
Can grow with only little moisture A few dissolved minerals These bacteria are photosynthetic and can convert CO2 from the atmosphere into the organic compounds They can convert N2 to NH3
Organisms from extreme environments are called extremophiles They provide the human race with important tools for processes to make useful chemicals and medicinals. Can be used in the recovery of metals from low-grade ores or in the desulfurization of coal or other fuels
Procaryotes have a simple structure with a single chromosome No nuclear membrane, no organelles, such as mitochondria, endoplasmic reticulum.
Eucaryotic cells have more than one chromosome (DNA molecule) in the nucleus. have a true nuclear membrane contain mitochondria Endoplasmic reticulum Golgi apparatus a variety of specialized organelles
Gram-negative cell (E. coli) has an outer membrane supported by a thin peptidoglycan layer. Gram-positive cells (Bacillus subtilis) do not have an outer membrane, have a very thick, rigid cell wall with multiple layers of peptidoglycan Mycoplasma (not gram positive or gram negative
Actinomycetes are bacteria, but, morphologically, resemble molds. Cyanobacteria(blue-green algae) have chlorophyll and fix CO2 into sugars. Anoxygenic photosynthetic bacteria(purple and green bacteria) have light-gathering pigments called bacteriochlorophyll.
Ribosomes are the site of protein synthesis, consists of 63% RNA and 37% protein. Storage granules are used as a source of key metabolites and contain polysaccharides, lipids, sulfur granules. Bacterial spores are produced as a resistance of adverse conditions such as high temperature, radiation, toxic chemicals. Volutin is granular intracellular structure, made of inorganic polymetaphosphates.
Archaebacteria have no peptidoglycan The nucleotide sequences in the ribosomal RNA are similar within the archaebacteria but different from eubacteria The lipid composition of the cytoplasmic membrane is very different for the two groups.
The nucleus of eucaryotic cells contains chromosomes as nuclear material (DNA molecules with associated small proteins), surrounded by a membrane. The nucleolus is the site of ribosome synthesis. Many chromosomes contain small amounts of RNA and basic proteins called histones attached to the DNA. Each chromosome contains a single linear DNA molecule on which the histones are attached.
Mitochondria are the powerhouses of a eucaryotic cell, where respiration and oxidative phosphorylation take place. The mitochondria contain a complex system of inner membranes called cristae. A mitochondria has its own DNA and protein-synthesizing machinery and reproduces independently.
The endoplasmic reticulum is a complex, convoluted membrane system leading from the cell membrane into the cell. The rough endoplasmic reticulum contains ribosomes and is the site of protein synthesis and modifications of protein structure after synthesis. The smooth endoplasmic reticulum is involved with lipid synthesis.
Lysosomes are very small membrane- bound particles that contain and release digestive enzymes. Peroxisomes carry out oxidative reactions that produce hydrogen peroxide. Glyoxysomes are very small membrane- bound particles that contain the enzymes of the glyoxylate cycle.
Golgi bodies are very small particles composed of membrane aggregates and are responsible for the secretion of certain proteins. Vacuoles are membrane-bound organelles of low density and are responsible for food digestion, osmotic regulation, and waste- product storage. Chloroplasts are relatively large, chlorophyll- containing, green organelles that are responsible for photosynthesis in photosynthetic eucaryotes, such as algae and plant cells.
Michael L. Shuler and Fikret Kargı, Bioprocess Engineering: Basic Concepts (2 nd Edition),Prentice Hall, New York, James E. Bailey and David F. Ollis, Biochemical Engineering Fundementals (2 nd Edition), McGraw- Hill, New York, 1986.