Dear Prince Okoroh,

When under anaerobic conditions lactate production is blocked the NADH produced in the glycolytic glyceraldehyde-3-phosphate dehydrogenase reaction cannot be reoxidized anymore. As a consequence the glycolytic pathway will come to a complete stand-still, unless the cell will have at its disposal metabolic alternatives. Otherwise it will perish. Certain organisms, such as yeast , are able to reduce the accumulating glyceraldehyde-3-phosphate via dihydroxyacetone-phosphate to glycerol phosphate which then is excreted in the form of glycerol after its dephosphorylation by an enzyme glycerol-phosphatase , but this alternative does not lead to any net ATP formation. The cells therefore will not survive for long. However, in trypanosomes this reaction may takes place inside peroxisome-like organelles, called glycosomes, and the intermediate glycerol-3-phosphate so formed is then converted to glycerol with the help of the enzyme glycerol kinase, which then leads to a net synthesis of ATP. As a result trypanosomes , which lack a lactate dehydrogenase, are able to carry out anaerobic glycolysis without lactate formation but excrete glycerol. This is just a survival pathway because in the end trypanosomes will will stop dividing.