Aspartases: Molecular Structure, Biochemical Function and Biotechnological Applications

Synthetic and Therapeutic Applications of Ammonia-lyases and Aminomutases

“…Undoubtedly, aspartase represents one of the earliest success stories of biocatalysis for industrial applications. Its high specificity and activity were immediately recognized and exploited in several industrial processes for the preparation of l -aspartic acid from fumaric acid and ammonium salts, comprehensively reviewed elsewhere. , The earliest applications employed wild-type E. coli cells immobilized on various supports, such as polyacrylamide, polyurethane, or carrageenan, with high productivity, good stability, and, most importantly, low cost. Subsequent improvements on this process involved the use of recombinant cells overproducing aspartase and the application of thermotolerant DALs with increased stability under the process conditions .…”

“…Aspartate ammonia-lyases (DALs), also known as aspartases, catalyze the reversible deamination of l -aspartic acid to fumaric acid. − They play a crucial role in bacterial nitrogen metabolism, and they belong to a broad and well-characterized superfamily (the “aspartase/fumarase” superfamily) with a characteristic tertiary and quaternary structure, as well as a similar active site architecture . However, other members of this superfamily are known to catalyze different C–N lyase reactions, C–O lyase reactions, and other unrelated transformations.…”

“…Considering this impressive variety of enzyme subclasses, with completely different mechanistic and structural features, a comprehensive report covering all the families mentioned above would be beyond the scope of this review. Several previous accounts and perspectives have already covered in detail the structure and mechanism of specific classes of ammonia-lyases − ,− ,,− and aminomutases. ,, Nevertheless, since great interest has been devoted to some of these families recently for their (potential or demonstrated) synthetic, industrial, or therapeutic applications, the present review intends to cover in detail only these subclasses: aspartate ammonia-lyases (section ), methylaspartate ammonia-lyases (section ), arylalanine ammonia-lyases (section ), and arylalanine aminomutases (section ), with specific emphasis on their applications (sections and ). A few members of these families have been recently demonstrated as valuable tools for the synthesis of high-value-added products (e.g., pharmaceuticals, agrochemicals, chiral building blocks) or for biotherapeutic applications in the treatment of specific diseases.…”

Immobilization of the Aspartate Ammonia‐Lyase from Pseudomonas fluorescens R124 on Magnetic Nanoparticles: Characterization and Kinetics

“…AALs play an important role in microbial nitrogen metabolism, and they have been widely studied and applied since the 70s to produce Asp in large quantities, which is an important compound in the artificial sweetener production, in the pharmaceutical industry, and in the enzymatic production of l ‐alanine being utilized in parenteral nutrition and as food additive [2,3] . Although the AAL of Pseudomonas fluorescens was isolated, [4,5] cloned and sequenced earlier, [6] the first extensively studied and applied AAL originated from Escherichia coli [7] . Aided by recombinant technologies, many AALs were identified and characterized since then [6,8–16] .…”

“…[ 2 , 3 ] Although the AAL of Pseudomonas fluorescens was isolated,[ 4 , 5 ] cloned and sequenced earlier, [6] the first extensively studied and applied AAL originated from Escherichia coli . [7] Aided by recombinant technologies, many AALs were identified and characterized since then. [ 6 , 8 , 9 , 10 , 11 , 12 , 13 , 14 , 15 , 16 ] All AALs are homotetrameric enzymes consisting of four identical active sites forming from sidechains of multiple monomeric chains of ∼52 kDa size.…”