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Volume 8
Journal of Biotechnology & Biomaterials
ISSN: 2155-952X
Biotech Congress 2018 & Enzymology 2018
March 05-07, 2018
Page 58
conference
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JOINT EVENT
20
th
Global Congress on
Biotechnology
3
rd
International Conference on
Enzymology and Molecular Biology
&
March 05-07, 2018 London, UK
Jennifer A Littlechild, J Biotechnol Biomater 2018, Volume 8
DOI: 10.4172/2155-952X-C2-090
Thermophilic enzymes with applications for industrial biocatalysis
T
here is an increasing demand for new enzymes with enhanced performance and/or novel functionalities that provide
savings in time, money and energy for industrial processes in the areas of high value chemical production and other
white biotechnology applications. Only a small proportion of nature’s catalysts have been utilised for industrial biotechnology.
The number of enzymes explored to date remains within the range of 1-2% of known biodiversity. A problem with using
enzymes for industrial biocatalysis reactions is often their stability under the harsh conditions employed. The use of naturally
thermostable enzymes isolated from hot environments are more stable to high temperatures, extremes of pH and exposure
to organic solvents. The projects HOTZYME and THERMOGENE have identified hydrolase and transferase enzymes of
industrial interest isolated from high temperature environments around the world. These have been isolated from thermophilic
bacterial and archaeal genomes and metagenomes. A selection of these novel thermostable enzymes including cellulases,
carboxylesterases, lactonases, epoxide hydrolases, transketolases, hydroxymethyl transferases and transaminases have been
characterized both biochemically and structurally. Transaminase enzymes have received special attention for the production
of chiral amines which are important building blocks for the pharmaceutical industries. These enzymes catalyse the reversible
transfer of an amino group from a donor substrate onto a ketone/aldehyde or sugar acceptor molecule. They can be subdivided
into 6 classes. The less studied class 4 (branched chain) (R) selective, class 5 (S) selective and class 6 (sugar) enzymes have
been identified. An example of the archaeal class 4 enzyme from
Archaeoglobus fulgidus
; a thermostable class 5 archaeal
transaminase from
Sulfolobus solfataricus
and class 6 sugar transaminase from
A. fulgidus
. Two new enzymes with interesting
substrate specificity and stereo-selectivity have been discovered which have already been demonstrated at industrial scale for
the production of new chiral chemical building blocks.
Figure 1:
Hexameric structure of branched chain transaminase from A. fulgidus. An inhibitor bound to the cofactor pyridoxal
phosphate at the active sites shown in spheres.
Jennifer A Littlechild
University of Exeter, UK