Chemoautotroph Bacteria Electron Electron Products donor acceptor Alcaligens and H五 02 H2O Pseudomonas sp Nitrobacter NO2 02 NO3,H2O Nitrosomonas NH4" 02 NO2,H2O Desulfovibrio H S042 H2O.H2S Thiobacillus denitrificans SO.H2S NO3 SO42-,N2 Thiobacillus ferrooxidans Fe2+ 02 F3+,H2O Nitrifying bacteria 2NH4+3O2→ 2 NO2-+2 H2O+4 H+132 Kcal
Chemoautotroph Nitrifying bacteria 2 NH4 + + 3 O2 2 NO2- + 2 H2O + 4 H+ + 132 Kcal Bacteria Electron donor Electron acceptor Products Alcaligens and Pseudomonas sp. H2 O2 H2O Nitrobacter NO2 - O2 NO3 - , H2O Nitrosomonas NH4 + O2 NO2 - , H2O Desulfovibrio H2 SO4 2- H2O. H2S Thiobacillus denitrificans S 0 . H2S NO3 - SO4 2- , N2 Thiobacillus ferrooxidans Fe 2+ O2 Fe 3+ , H2O
6.3 Uptake of nutrients Nutrient molecules frequently cannot cross selectively permeable plasma membranes through passive diffusion and must be transported by one of three major mechanisms involving the use of membrane carrier proteins
Nutrient molecules frequently cannot cross selectively permeable plasma membranes through passive diffusion and must be transported by one of three major mechanisms involving the use of membrane carrier proteins. 6.3 Uptake of nutrients
1.Phagocytosis-Protozoa 2.Permeability absorption-Most microorganisms 。 Passive transport simple diffusion Facilitated diffusion ·Active transport ·Group translocation
1. Phagocytosis – Protozoa 2. Permeability absorption – Most microorganisms • Passive transport simple diffusion • Facilitated diffusion • Active transport • Group translocation
Passive diffusion Passive diffusion is the process in which molecules move from a region of higher concentration to one of lower concentration as a result of random thermal agitation.A few substances,such as glycerol,can cross the plasma membrane by passive diffusion
Passive diffusion is the process in which molecules move from a region of higher concentration to one of lower concentration as a result of random thermal agitation. A few substances, such as glycerol, can cross the plasma membrane by passive diffusion. Passive diffusion
Facilitated diffusion The rate of diffusion across selectively permeable membranes is greatly increased by the use of carrier proteins,sometimes called permeases,which are embedded in the plasina membrane.Since the diffusion process is aided by a carrier,it is called facilitated diffusion.The rate of facilitated diffusion increases with the concentratioti gradient much more rapidly and at lower concentrations of the diffusing molecule than that of passive diffusion
The rate of diffusion across selectively permeable membranes is greatly increased by the use of carrier proteins, sometimes called permeases, which are embedded in the plasina membrane. Since the diffusion process is aided by a carrier, it is called facilitated diffusion. The rate of facilitated diffusion increases with the concentratioti gradient much more rapidly and at lower concentrations of the diffusing molecule than that of passive diffusion Facilitated diffusion