Already have an account? Get multiple benefits of using own account!
Login in your account..!
Remember me
Don't have an account? Create your account in less than a minutes,
Forgot password? how can I recover my password now!
Enter right registered email to receive password!
Active Transport
We have mentioned above that Transmembrane potential develops due to active transport of ions (H+) outside the cell. Since this transport takes place again& a concentration gradient it utilises energy of hydrolysis of ATP. The proton motive force generated by proton pumping provides the driving force for the transport of solutes including cations, anions, amino acids and sugars. Electrical potential and pH measurements of intact plant cells have suggested that proton pumps are localised on the plasma membrane. The plant plasma membrane ATPase is a transmembrane protein composed of a single polypeptide chain of 100 KD. The most possible coupling mechanism between ATP hydrolysis and proton transport is shown in Figure.
Figure: Simplified picture of active transport.
The enzyme exists in two conformations differing in catalytic and transport properties. In conformation I, the transport site faces the cytoplasm and has high affinity for protons. In conformation II the transport site is externally oriented and has low affinity for protons. The enzyme is forced to alternate between these two conformations and to bind and release the transported proton because neither conformation can affect the complete catalytic cycle. In conformation I, the enzyme acts as a kinase; after binding a proton it catalyses the formation of phosphorylated intermediate. In the new state (conformation II) if acts as a phosphatase and after releasing the proton it returns to its original state, conformation I.
Penicillin, discovered by the Scottish doctor Alexander Fleming, in 1928, is a drug that inhibits enzymes essential for the synthesis of peptidoglycans, a constituent of the bacter
how to identified plants
NEUROGLI A CELLS (Rudolf Virchow, 1846) - Occurs in the C.N.S. The cells are less than neurons. Neuroglia cells are of four types - (i) Oligodendrocytes - Occ
Solubility and physical properties of protiens Simple proteins Conjugated proteins Derived proteins
Explain about the Multiple Sclerosis This is a disease characterised by the loss of myelin, largely in motor tracts but also in sensory tracts. The loss of myelin is not unifor
Q. What are sarcomeres? Sarcomeres are the contractile units of the muscle tissue formed of alternating myosin blocks (thick filaments) and actin blocks (thin filaments). Sever
PROJECTS THAT HAVE TO BE DONE IN SCHOOL ABOT PICICULTURE
In what way does overgrazing lead to soil erosion?
Q. Guiding and overseeing actions of Consciousness? Guiding and overseeing actions: Consciousness connects brain and body states with external occurrences. In order to functio
How does the contraceptive diaphragm work? What are the limitations of this contraceptive method? The contraceptive diaphragm is an artifact made of latex or plastic that when
Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!
whatsapp: +91-977-207-8620
Phone: +91-977-207-8620
Email: [email protected]
All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd