Please explain Role of Sedoheptulose 1 7Blsphosphatase What

Please explain

Role of Sedoheptulose 1, 7-Blsphosphata.se What effect on the cell and the organism might result from a defect in sedoheptulose 1, 7-bisphosphatase in (a) a human hepatocyte and (b) the leaf cell of a green plant?

Solution

Sedoheptulose-bisphosphatase (also sedoheptulose-1,7-bisphosphatase or SBPase)

a,

In the human hepatocyte NADPH is produced by the pentose phosphate pathway- for which sedoheptulose 1,7-bisphosphatase activity is essential which is needed for the reductive steps in the synthesis of fatty acids, triacylglycerols, and sterols. Without this source of NADPH, all these processes may be inhibited. Cells will be unable to synthesize lipids and other reduced products.

b,

The lack of sedoheptulose 1,7-bisphosphatase would prevent the functioning of the Calvin cycle; the enzyme which is essential in the series of reactions that convert triose phosphates into ribulose 1,5- bisphosphate, without generation of ribulose 1,5-bisphosphate, so the Calvin cycle is effectively blocked and there is no acceptor for carbondioxide in the first step in the pathway. Therefore leaf cell would be incapable of fixing carbondioxide.