A new approach for efficient synthesis of phenyllactic acid from L-phenylalanine: Pathway design and cofactor engineering

Abstract

Phenyllactic acid (PLA), a novel biological antiseptic agent with broad and effective antimicrobial activity, finds wide applications in the food processing field. In this work, a new approach for biocatalytic synthesis of PLA from l‐phenylalanine (Phe) was constructed. First, selection of l‐lactate dehydrogenase (LDH) was done to achieve the efficient synthesis of PLA from phenylpyruvic acid (PPA); Second, l‐amino acid deaminase (l‐AAD) and LDH were co‐expressed to achieve the synthesis of PLA from Phe; Finally, formate dehydrogenase (FDH) was overexpressed to accelerate the regeneration of cofactor NADH from NAD, which is necessary for the biocatalysis of LDH. By this biocatalytic system, 30 g·L−1 Phe was transformed into PLA with 100% conversion ratio in 12 hr. This work developed a new and efficient biocatalytic approach for PLA production with Phe as a cheap substrate, which provides an alternative for PLA production in a green manner. Practical applications PLA is a novel antimicrobial compound with broad inhibition activity and has less side‐effect on the health of human being. It is an ideal antiseptic that has received much attention in the food industry, for the control of microbial contaminants. In addition, PLA can be used as feed additives to replace antibiotics in livestock feeds. The newly established biosynthetic system in this work may be a promising technique for the industrial production of PLA due to high production and high efficiency.

High-Yielding Protocatechuic Acid Synthesis from l-Tyrosine in Escherichia coli

“…LAAD from P. mirabilis is a FAD-containing enzyme, which catalyzes the deamination of l -amino acids into their corresponding α-keto acids. ,− The deamination of l -tyrosine led to the synthesis of 4-hydroxyphenylpyruvate (HPPA), which can be further converted into 3,4-dihydroxyphenylpyruvate (DHPPA) by the endogenous hydroxylase of HpaBC from E. coli .…”

Enzyme assembly guided by SPFH‐induced functional inclusion bodies for enhanced cascade biocatalysis

“…As a novel biological antiseptic agent with broad and effective antimicrobial activity, phenyllactic acid has been widely used in the food processing field. Recently, we have constructed a new biocatalytic approach for phenyllactic acid synthesis from l ‐phenylalanine by co‐expression of l ‐amino acid deaminase (L‐AAD) and l ‐lactate dehydrogenase (LDH; Wang et al, 2018). As shown in Figure 2a, l‐aad is first used to catalyze the synthesis of phenylpyruvic acid from l ‐phenylalanine; then, LDH catalyzes the formation of phenyllactic acid from phenylpyruvic acid.…”

Point mutations that boost aromatic amino acid production and CO 2 assimilation in plants

“…Further careful comparisons of GC-MS traces between genotypes revealed that a few previously unidentified peaks appeared in both sotaB4 and sotaA4 mutants but not in Col-0 samples; on the basis of the National Institute of Standards and Technology library search and subsequent comparison to respective authentic standards, these peaks were identified as PPY, the keto acid of Phe produced by aromatic aminotransferases (21)(22)(23), as well as phenylacetate and phenyllactate, which are both likely derived from PPY (Fig. 3B) (24,25). Notably, the levels of PPY and PPY derivatives, detected in sota mutants, positively correlated with the Phe level (Fig.…”