In October, the sun shines for at least 7 hours per day but brace yourself for rain as there are on average 6 days of rainfall during the month. Around 70mm of rain falls throughout October with temperatures generally settling between 14 Â°C and 26 Â°C.
For example, ATP allosterically inhibits phosphofructokinase, but it activates the functionally opposite enzyme fructose-1,6-bisphosphatase (see slide 7.5.3). Similarly, phosphorylation inhibits glycogen synthase but activates glycogen phosphorylase, which degrades glycogen (slide 8.4.1).llosteric regulation of phosphofructokinase by AMP. To accomplish the stimulation of phosphofructokinase, AMP interacts with the enzyme at an allosteric binding site, that is, a site that is distant and functionally distinct from the active site.
Phosphofructokinase (PFK) is a glycolytic enzyme that catalyzes the irreversible transfer of a phosphate from ATP to fructose-6-phosphate: fructose-6-phosphate + ATP fructose-1,6-bisphosphate + ADP. In part because of the irreversible nature of this step in glycolysis, PFK is the key regulatory enzyme for glycolysis. When ATP levels are high in the cell, the cell no longer needs metabolic energy production to occur. In this case, PFK's activity is inhibited by allosteric regulation by ATP itself, closing the valve on the flow of carbohydrates through glycolysis. Recall that allosteric regulators bind to a different site on the enzyme than the active (catalytic) site.