Two-enzyme system for the synthesis for 1-lauroyl-rac-glycerophosphate (lysophosphatidic acid) and 1-lauroyl-dihydroxyacetonephosphate

An enzymatic alternative for the synthesis of nucleoside 5'-monophosphates

A new procedure was carried out for the synthesis of nucleoside 5'-monophosphates, involving the use of two enzymes. The first step applied phospholipase D from Streptomyces netropsis and phosphatidylcholine as phosphatidyl donor, to give 5'-(3-sn-phosphatidyl) nucleosides (C, U, A, I). These were selectively hydrolysed in the second step by the action of phospholipase C from Bacillus cereus to produce the respective 5'-nucleotides. Application of this methodology on a preparative scale conducted to 5'-adenosine monophosphate in 63% overall yield from adenosine. The regioselectivity of these enzymes avoids protection steps, the overall synthesis is performed under mild reaction conditions and product isolation is easily achieved.

Enzymatic modification of phospholipids for functional applications and human nutrition

Rapid progress in biochemistry of phospholipids and evolution of modern bioengineering has brought forth a number of novel concepts and technical advancements in the modification of phospholipids for industrial applications and human nutrition. Highlights cover preparation of novel phospholipid analogs based on the latest understanding of pivotal role of phospholipids in manifold biological processes, exploration of remarkable application potentials of phospholipids in meliorating human health, as well as development of new chemical and biotechnological approaches applied to the modification of phospholipids. This work reviews the natural occurrence and structural characteristics of phospholipids, their updated knowledge on manifold biological and nutritional functions, traditional and novel physical and chemical approaches to modify phospholipids as well as their applications to obtain novel phospholipids, and brief introduction of the efforts focusing on de novo syntheses of phospholipids. Special attention is given to the summary of molecular structural characteristics and catalytic properties of multiple phospholipases, which helps to interpret experimental phenomena and to improve reaction design. This will of course provide fundamental bases also for the development of enzymatic technology to produce structured or modified phospholipids.

Activity of phospholipase C in two-phase systems

Although phospholipase C (PLC) is known to be activated by water-insoluble organic solvents, most activity assays have been designed to work in an aqueous milieu. Here a sensitive method is described for the determination of PLC activity in two-phase systems. The assay is based on the hydrolysis of phosphatidylcholine (PC) in chloroform/buffer. The initial rates of the reaction are determined by densitometric quantification of the product 1,2-diacylglycerol after its separation by high-performance TLC and staining with a CuSO4/H3PO4 or p-methoxybenzaldehyde/H2SO4 reagent. The method is examined for the determination of Vmax and Km values of PCs with varying length acyl chains (C10-C18). The comparison of the kinetic parameters with the Vmax and Km values of the same substrates in the conventional titrimetric assay, using sodium deoxycholate for micellization of PC, demonstrates the high efficiency of PLC in the two-phase emulsion system.