nonprocessivity

Nonprocessivity is a term used in biology and genetics to describe an enzyme's inability to continue making multiple reaction cycles with a single molecule of substrate without disassociating from it first.

In molecular biology, processivity is often used to describe enzymes that can bind to and continue to catalyze multiple reaction cycles with a single substrate molecule before dissociating from it. Nonprocessive enzymes, on the other hand, bind to the substrate, perform one catalytic event, and then dissociate from the substrate, requiring multiple turnovers of the enzyme-substrate complex to achieve the desired outcome.

Nonprocessive enzymes often have a lower efficiency and can be more costly to use, as the enzyme-substrate complex needs to be re-established multiple times to achieve the desired level of reaction completion. This, however, can offer flexibility as the enzyme reaction time can be adjusted to meet specific needs of the experimentation.

Examples of nonprocessive enzymes include the linear DNA polymerases and the classical RNA polymerases. These enzymes are essential in the mechanisms of transcription and replication but in general the nonprocessive nature allows them to be highly specific which is a key requirement for DNA based techniques such as PCR and sequencing.

In summary, nonprocessive enzymes are crucial in nearly all types of biochemical reactions and transformations occurring within living organisms, but their efficiency issues related to substrate and enzyme well-timed activations bear the likelihood of lot multiplicity and trial by error to initiate output from quality substrate. This limitation to progressive mechanism affords specificity, efficiency, and other forms of required enzymatic characteristics in life sciences.