Micellar enzymology: Potentialities in applied areas (biotechnology)

Martínek, Karel; Березин, И.В.; Khmelnitski, Yurii L.; Klyachko, N. L.; Levashov, A. V.

doi:10.1135/cccc19872589

Cited by 46 publications

(21 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Furthermore, the possibility of increasing concentration of both enzyme and substrate is also improved at the enhanced interfacial region [14] (Scheme 1), probably because of alteration in partition coefficients. [6,9,22] As it was found that the lipase activity is larger in series II surfactants (4)(5)(6) relative to corresponding surfactants of series I and III, we can explain this from the present study exclusively on the basis of the head-group area ( Table 1). Although the differences in A min value did not appear to be significant in some cases, it is probably sufficient enough to affect the enzyme activity.…”

Section: Resultsmentioning

confidence: 55%

“…[1][2][3][4] Lipases, a class of surface-active enzymes, [1] are widely exploited in diverse transformations in w/o microemulsions. [1,[5][6][7] The catalytic efficiencies of these enzymes are believed to be dependent primarily on the local concentrations of water and other ions present in the vicinity of the enzyme.…”

Section: Introductionmentioning

confidence: 99%

“…Enzymology in self-organized aggregates such as water-inoil (w/o) microemulsions has been an area of interest for several decades, because of its potential biotechnological applications. [1][2][3][4] Lipases, a class of surface-active enzymes, [1] are widely exploited in diverse transformations in w/o microemulsions. [1,[5][6][7] The catalytic efficiencies of these enzymes are believed to be dependent primarily on the local concentrations of water and other ions present in the vicinity of the enzyme.…”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Head‐Group Size or Hydrophilicity of Surfactants: The Major Regulator of Lipase Activity in Cationic Water‐in‐Oil Microemulsions

Das

Roy

Mitra

et al. 2005

Chemistry A European J

View full text Add to dashboard Cite

To determine the crucial role of surfactant head-group size in micellar enzymology, the activity of Chromobacterium Viscosum (CV) lipase was estimated in cationic water-in-oil (w/o) microemulsions of three different series of surfactants with varied head-group size and hydrophilicity. The different series were prepared by subsequent replacement of three methyl groups of cetyltrimethylammonium bromide (CTAB) with hydroxyethyl (1-3, series I), methoxyethyl (4-6, series II), and n-propyl (7-9, series III) groups. The hydrophilicity at the polar head was gradually reduced from series I to series III. Interestingly, the lipase activity was found to be markedly higher for series II surfactants relative to their more hydrophilic analogues in series I. Moreover, the activity remained almost comparable for complementary analogues of both series I and III, though the hydrophilicity was drastically different. Noticeably, the head-group area per surfactant is almost similar for comparable surfactants of both series I and III, but distinctly higher in case of series II surfactants. Thus the lipase activity was largely regulated by the surfactant head-group size, which plays the dominant role over the hydrophilicity. The increase in head-group size presumably allows the enzyme to attain a flexible conformation as well as increase in the local concentration of enzyme and substrate, leading to the higher efficiency of lipase. The lipase showed its best activity in the microemulsion of 6 probably because of its highest head-group size. Furthermore, the observed activity in 6 is 2-3-fold and 8-fold higher than sodium bis(2-ethyl-1-hexyl)sulfosuccinate (AOT) and CTAB-based microemulsions, respectively, and in fact highest ever in any w/o microemulsions.

show abstract

Section: Resultsmentioning

confidence: 55%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Head‐Group Size or Hydrophilicity of Surfactants: The Major Regulator of Lipase Activity in Cationic Water‐in‐Oil Microemulsions

Das

Roy

Mitra

et al. 2005

Chemistry A European J

View full text Add to dashboard Cite

show abstract

“…In this regard the fact that uricase is concentrated within a microbody, which also contains a potential Oz-generating mechanism (catalase; Hanks et al 1981), should not be overlooked. Furthermore, the kinetic properties of many enzymes have been shown to be markedly altered through their confinement at high concentration in lipophyllic micellar structures (Martinek et al 1987) which might be likened, to some extent, to microbodies. The enzyme has been successfully puri-fled from nodules of a number of ureide-forming species (e.g.…”

Section: Discussionmentioning

confidence: 99%

Effect of oxygen pressure on synthesis and export of nitrogenous solutes by nodules of cowpea

Atkins

Dakora

Storer

1990

Planta

View full text Add to dashboard Cite

Nodules of cowpea plants (Vigna unguiculata (L.) Walp. cv. Vita 3 :Bradyrhizobium CB756) cultured for periods of 23 d with their root systems maintained in atmospheres containing a range of partial pressures of O2 (pO2; 1-80%, v/v, in N2) formed and exported ureides (allantoin and allantoic acid) as the major products of fixation at all pO2 tested. In sub-ambient pO2 (1 and 2.5%) nodules contained specific activities of uricase (urate: O2 oxidoreductase; EC 1.7.3.3) and allantoinase (allantoin hydrolyase; EC 3.5.2.5) as much as sevenfold higher than in those from air. On a cell basis, uninfected cells in nodules from 1% O2 contained around five times the level of uricase. Except for NAD: glutamate synthase (EC 1.4.1.14), which was reduced in sub-ambient O2, the activities of other enzymes of ureide synthesis were relatively unaffected by pO2. Short-term effects of pO2 on assimilation of fixed nitrogen were measured in nodules of air-grown plants exposed to subambient pO2 (1, 2.5 or 5%, v/v in N2) and(15)N2. Despite a fall in total(15)N2 fixation, ureide synthesis and export was maintained at a high level except in 1% O2 where formation was halved. The data indicate that in addition to the structural and diffusional adaptations of cowpea nodules which allow the balance between O2 supply and demand to be maintained over a wide range of pO2, nodules also show evidence of biochemical adaptations which maintain and enhance normal pathways for the assimilation of fixed nitrogen.

show abstract

“…When surfactants assemble in oil , the aggregate is referred to as a reverse micelle. In a reverse micelle, the hydrophilic heads of the surfactants are in the core of the micelle and the hydrophobic tails maintain favorable contact with oil [6][7][8]. The most commonly used surfactants are thiols, oleic acid, laurate salts.…”

mentioning

confidence: 99%

Heat transfer measurement in oil-based nanofluids.

Liu¹

View full text Add to dashboard Cite

Micellar enzymology: Potentialities in applied areas (biotechnology)

Cited by 46 publications

References 0 publications

Head‐Group Size or Hydrophilicity of Surfactants: The Major Regulator of Lipase Activity in Cationic Water‐in‐Oil Microemulsions

Head‐Group Size or Hydrophilicity of Surfactants: The Major Regulator of Lipase Activity in Cationic Water‐in‐Oil Microemulsions

Effect of oxygen pressure on synthesis and export of nitrogenous solutes by nodules of cowpea

Heat transfer measurement in oil-based nanofluids.

Contact Info

Product

Resources

About