Candida sp. lipase

Table 11.1-23. Lipase-catalyzed enantiomer- and enantiotopos-differentiating alcoholysis of carboxylic acid esters and anhydrides, alcoholysis or hydrolysis of oxazolin-2-ones, and esterification of carboxylic acids (PPL pig pancreas lipase, PCL Pseudomonas cepacia lipase, ANL Aspergillus niger lipase, CSL Candida sp. lipase, Candida cylindracea lipase, CAL-B Candida antarctica B lipase, CRL Candida rugosa lipase).

As a rule of thumb, the most widely used lipases may be characterized according to the steric requirements of their preferred substrate esters (Fig. 2.13). Whereas Aspergillus sp. lipases are capable of accepting relatively bulky substrates and therefore exhibit low selectivities on narrow ones, Candida sp. lipases are more versatile in this regard. Both the Pseudomonas and Mucor sp. lipases have been found to be highly selective on substrates with limited steric requirements and hence are often unable to accept bulky compounds. Thus, substrates which are recognized with moderate selectivities by a Candida lipase, are usually more... 

In conventional synthetic transformations, enzymes are normally used in aqueous or organic solvent at moderate temperatures to preserve the activity of enzymes. Consequently, some of these reactions require longer reaction times. In view of the newer developments wherein enzymes can be immobilized on solid supports [183], they are amenable to relatively higher temperature reaction with adequate pH control. The application of MW irradiation has been explored with two enzyme systems namely Pseudomonas lipase dispersed in Hyflo Super Cell and commercially available SP 435 Novozym (Candida antarctica lipase grafted on an acrylic resin). 

Systems such as Pseudomonas lipase dispersed inside Hyflo Supercell (a diatoma-ceous silica of pH 8.5-9) and SP 435 Novozym (Candida antarctica lipase grafted on an acrylic resin) are thermally stable and have optimum activity in the range 80-100 °C. They can therefore be used with conventional or microwave heating if the temperature is strictly controlled. 

In addition to cutinases, various lipases, such as from C. antarctica, Candida sp. [13, 47], Thermomyces lanuginosus [2, 14, 15, 55, 56], Burkholderia (formerly Pseudomonas) cepacia [57] and esterases from Pseudomonas sp. (serine esterase) [58] and Bacillus sp. (nitrobenzyl esterases) [59, 60], have shown PET hydrolase... 

Although lipases from Pseudomonas are usually the catalysts of choice for primary alcohols, 2-(2-furyl)-propan-l-ol (Scheme 4.8 7 n = 0 with instead of S) actually gives a higher E (E = 20) with Candida antarctica lipase (CALB) than it does with Pseudomonas sp. lipase (PSL) (E = 2) on acylation with vinyl acetate in pentane [78]. 

TIL Thermomyces lanuginosus lipase, RdL Rhizopus delemar lipase, RnL Rhizopus niveus lipase, MmE Mucor miehei esterase, PsL Pseudomonas sp. lipase, MmL Mucor miehei lipase, RoL Rhizopus orvzae lipase, CaLA Candida antarctica lipase A, CaLB Candida antarctica lipase B, PLE Pig liver esterase, EP Enteropeptidase, PKA Porcine kidney acylase, CE Cholesterol esterase Figure 8.1 (S)-Selective enzyme hits from hydrolase screening. ... 

Lipase-catalyzed intermolecular condensation of diacids with diols results in a mixture of macrocyclic lactones and linear oligomers. Interestingly, the reaction temperature has a strong effect on the product distribution. The condensation of a,CO-diacids with a,(0-dialcohols catalyzed by Candida cyiindracea or Pseudomonas sp. lipases leads to macrocyclic lactones at temperatures between 55 and 75°C (91), but at lower temperatures (<45°C) the formation of oligomeric esters predominates. Optically active trimers and pentamers can be produced at room temperature by PPL or Chromobacterium viscosum lipase-catalyzed condensation of bis (2,2,2-trichloroethyl) (+)-3-methyladipate and 1,6-hexanediol (92). 

In addition, Itoh and coworkers have reported that acylation of the alcohol was accomplished by three types of enzymes Candida Antarctica lipase (CAL, Novozym 435), lipase QL Alcalgenes sp.), and lipase PS Pseudomonas cepacia). Scheme 10.5. The desired acetate showed extremely high enantioselectivity, but no reaction took place when lipase (CRL, Candida rugosa) or Procine liver lipase (PPL) was used as the catalyst in the ionic liquid (Table 10.3). 

A total synthesis of 1,3-dideoxynojirimycin starting from cyclopentadiene was proposed by Johnson et al. [206]. Photooxidation of cyclopentadiene and reductive workup with thiourea generates c/ -cyclopent-2-ene-l,4-diol, which is monoacylated with high enantioselectivity (>99% ee) with isoprenyl acetate and Candida antarctica lipase B (Novo Nordisk SP 435) to give 461. After silylation of 461 and subsequent treatment with KOH and oxidation, enantiomerically pure enone 462 is obtained [207]. 

Five-membered unsubstituted lactone, y-butyro-lactone (y-BL), is not polymerized by conventional chemical catalysts. However, oligomer formation from y-BL was observed by using PPL or Pseudomonas sp. lipase as catalyst.1523 157 d-Valerolactone (<3-VL, six-membered) was polymerized by various lipases of different origin to give the polymer with Mn of several thousands.148 Another six-membered lactone, l,4-dioxan-2-one, was polymerized by Candida antarctica lipase (lipase CA) to give the polymer with Mw higher than 4 x 104.158 The resulting polymer is expected as a metal-free polymeric material for medical applications. 

One of the reactions catalyzed by esterases and lipases is the reversible hydrolysis of esters (Figure 1 reaction 2). These enzymes also catalyze transesterifications and the asymmetrization of meso -substrates (Section 13.2.3.1.1). Many esterases and lipases are commercially available, making them easy to use for screening desired biotransformations without the need for culture collections and/or fermentation capabilities. As more and more research has been conducted with these enzymes, a less empirical approach is being taken due to the different substrate profiles amassed for various enzymes. These profiles have been used to construct active site models for such enzymes as pig liver esterase (PLE) (EC 3.1.1.1) and the microbial lipases (EC 3.1.1.3) Pseudomonas cepacia lipase (PCL), formerly P.fluorescens lipase, Candida rugosa lipase (CRL), formerly C. cylindracea lipase, lipase SAM-2 from Pseudomonas sp., and Rhizopus oryzae lipase (ROL) [108-116]. In addition, x-ray crystal structure information on PCL and CRL has been most helpful in predicting substrate activities and isomer preferences [117-119]. 

The application of ionic liquids in lipase biocatalysis has not remained entirely restricted to CaLB, PcL or CrL. Other lipases have been used in ionic liquids for ester synthesis such as Candida antarctica lipase A (CaLA) [15,16], Thermomyces lanuginosus lipase [17] (TLL), Rhizomucor miehei lipase (PmL), Pseudomonas fluorescens lipase (PJL) [18], Pig pancreas lipase (PpL) [17] and Alcaligenes sp. lipase (A5 L) [16]. 

Lipases have been used to effect the enantioselective esterification of cyanohydrins or the enantioselective hydrolysis of cyanohydrin esters. This works for aldehyde cyanohydrins. Selective (S)-cyanohydrin esterification is effected by the enzyme from Pseudomonas sp. [11], There is also an example of selective (R)-cyanohydrin esterification by Candida cylindracea lipase [12]. Effenberger has shown the feasibility of this approach in principle to produce a number of enantiopure cyanohydrins derived from aldehydes. In situ derivatization with racemization as shown in Fig. 7 is possible, resulting in theoretically 100% yield of the desired enantiomer [13]. Ketone cyanohydrins, which are tertiary alcohols, do not easily undergo this reaction. 

Pseudomonas sp. and Candida rugosa lipases Clay Synthesis of lipids from tricaprylin and trilinolein [53]... 

Lipase Candida antarctica, Candida sp. XPS, release of oligomers [50, 51]... 

The lipases most used until now are the commercially supplied pig pancreas lipase (PPL), Pseudomonas cepacia lipase (PCL) or P. Jluorescens lipase (PFL), Candida cylindracea (CCL) or C. rugosa lipase (CRL), Pseudomonas sp. lipase (PSL), increasingly Candida antarctica B lipase (CAL-B) and to a lesser extent further lipases mentioned in Tables 11.1-10 to 11.1-25, and cholesterol esterase (CE). CAL-B is a recombinant protein produced in AspergiUus oryzae accepting a broad range of substrates and conditions. A special group of hydrolases, which are considered as lipases, are the cholesterol esterases (CE), found in mammals and microorganisms1113. ... 

Table 11.1-12. Lipase-catalyzed enantiotopos-differentiating hydrolysis of prochiral acyclic and cyclic dicarboxylic acid diesters in aqueous solution (CCL Candida cylindracea lipase, PPL pig pancreas lipase, PSL Pseudomonas sp. lipase, CVL Chromobacterium viscosum lipase,...

The usefulness of lipases for the enantiomer-differentiating hydrolysis of carboxylic acid esters and lactones is impressively demonstrated by examples 1-S9 of Table 11.1-13. This broad substrate spectrum is covered mainly by lipases from Candida cylindracea (rugosa), pig pancreas and several Pseudomonas sp. lipases. Carboxylic acid esters having the alkoxycarbonyl group attached to a secondary, tertiary or even quaternary carbon atom are substrates. Thus, in contrast to... 

MML Mucor miehei lipase, CAL-B Candida antarctica B lipase, LIP Pseudomonas sp. lipase -Toyobo, HSL Humicola sp. lipase). 

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