Effects of fluid shear on immobilized enzyme kinetics

Harrington, Tyler; Gainer, John L.; Kirwan, Donald J.

doi:10.1016/0141-0229(91)90073-j

Cited by 19 publications

(9 citation statements)

References 22 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Similar shear stability at low temperatures has been observed with other enzymes. 16 When the temperature was increased to 25°C (Fig. l), once again, the nonsheared DS solution experienced little loss of activity; the shape of this inactivation curve was as predicted by Eq.…”

Section: Resultsmentioning

confidence: 96%

Effect of shear on the inactivation kinetics of the enzyme dextransucrase

Lencki

Tecante

Choplin

1993

Biotech & Bioengineering

View full text Add to dashboard Cite

An inactivation model previously developed to characterize the rate of enzyme activity loss in unstirred solutions was extended to take into account orthokinetic interactions resulting from convective mixing. A synergistic relationship between shear rate and temperature was observed; the rate of inactivation of the enzyme dextransucrase was unaffected by the action of shear below 25 degrees C, but was increased by the shear rate at 30 degrees C. Shear rate does not appear to influence the equilibrium between native and denatured dextransucrase either directly in solution or indirectly by augmenting the turnover of the gas-liquid interface. However, a second-order plot of the inverse of relative activity (A(O)/A) versus Gt (shear rate x time) of dextransucrase at a constant temperature was linear because of the influence of shear on the coagulation of the denatured enzyme. The addition of 0.01 g L(-1) of polyethylene glycol (MW 20,000) blocked this coagulation reaction, thereby completely inhibiting the shear-induced inactivation of dextransucrase at 30 degrees C.

show abstract

Section: Resultsmentioning

confidence: 96%

Effect of shear on the inactivation kinetics of the enzyme dextransucrase

Lencki

Tecante

Choplin

1993

Biotech & Bioengineering

View full text Add to dashboard Cite

show abstract

“…In passing, Harrington et al (1991) showed for several immobilised enzymes, shear had no effect on the maximum reaction velocity nor on the Michaelis constant. This suggested that shear at levels found in industrial processes were unlikely to distort the structure of a globular protein significantly despite the earlier report of Tirrell and Middleman (1975).…”

mentioning

confidence: 99%

Effects of shear on proteins in solution

2010

View full text Add to dashboard Cite

The effects of "shear" on proteins in solution are described and discussed. Research on this topic covers many decades, beginning with investigations of possible denaturation of enzymes during processing, whilst more recent concerns are how the quality of therapeutic proteins might be affected by shear or shear related effects.The paradigm that emerges from most studies is that shear in the fluid mechanical sense is unlikely by itself to damage most proteins and that interfacial phenomena are critically important. In particular, moving gas-liquid interfaces can be very deleterious. Aggregation of therapeutic proteins on nanoparticles shed from solid surfaces is a recent concern because of potential consequences on patient safety. It is clear that labeling such damage as "shear" is a mistake as this inhibits clear investigations of, and thinking about, the true causes of damage to proteins in solution during processing.

show abstract

“…The effect of high recirculation flow rate on the enzyme (Fig. 3) may be attributed to the inactivation due to shear stress (Charm & Wong, 1981;Harrington, Gainer, & Kirwan, 1991). The lowest J residual (31.45%) was recorded at initial permeate flow at level Àa (1.6 mL/min) while the highest (110.32%) was an outlier which is probably due to a loosening of the screw clip used to regulate permeate flow rate with time.…”

Section: Wpi Hydrolysismentioning

confidence: 89%

“…Likewise, too low a recirculation flow rate led to pile-ups of the substrate at the membrane layer further aggravating permeate flux declines. Loss of enzyme activity at a higher flow rate may be attributed to the effect of shear forces in inactivation (Charm & Wong, 1981;Harrington et al, 1991). Fig.…”

Section: Residual Enzyme Activity (A Residual )mentioning

confidence: 97%