A predominant β-CGTase G1 engineered to elucidate the relationship between protein structure and product specificity

Low reaction yields and the high cost of obtaining a single type of pure CD make γ-CD costly. Using rational design and with the aid of 3D modeling structures, recombinant CGTase from Bacillus sp. G1 was molecularly engineered with the aim of producing a higher percentage of γ-CD. A single mutatio...

Full description

Bibliographic Details
Main Authors: Goh, Kin Mau, Mahadi, Nor Muhammad, Hassan, Osman, Rahman, Raja Noor Zaliha Raja Abdul, Illias, Rosli Md
Format: Article
Published: Elsevier B.V. 2009
Subjects:
_version_ 1796854193978343424
author Goh, Kin Mau
Mahadi, Nor Muhammad
Hassan, Osman
Rahman, Raja Noor Zaliha Raja Abdul
Illias, Rosli Md
author_facet Goh, Kin Mau
Mahadi, Nor Muhammad
Hassan, Osman
Rahman, Raja Noor Zaliha Raja Abdul
Illias, Rosli Md
author_sort Goh, Kin Mau
collection ePrints
description Low reaction yields and the high cost of obtaining a single type of pure CD make γ-CD costly. Using rational design and with the aid of 3D modeling structures, recombinant CGTase from Bacillus sp. G1 was molecularly engineered with the aim of producing a higher percentage of γ-CD. A single mutation at subsite -3, denoted H43T, was found to increase γ-CD production from 10% to approximately 39% using tapioca starch. This novel increment was probably the result of reduced steric hindrance to the formation of γ-CD because of the shortened side chain together with the shortened loop at positions 86-89, at substrate-binding subsite -3. A mutation (Tyr188 → Trp) and a deletion at loop 139-144 showed little effect on product specificity; however, mutagenesis at these sites affected cyclization, coupling and hydrolysis activities as well as the kinetic properties of the mutant CGTase. Based on rational design, three further mutations of the mutant H43T (denoted H43T/Δ(139-144)/S134T/A137V/L138D/V139I, H43T/S85G and H43T/Y87F) were constructed and produced γ-CD with yields of 20%, 20% and 39%, respectively. The mutant H43T/Δ(139-144)/S134T/A137V/L138D/V139I had very low cyclization and coupling activities, however their hydrolysis activity was retained. Double mutation (H43T/S85G) caused the enzyme to exhibit higher starch hydrolysis activity, approximately 26 times higher than the native CGTase G1. Although the mutants H43T and H43T/Y87F could produce the same percentage (39%) of γ-CD, the latter was more efficient as the total amount of CD produced was higher based on the Vmax and kcat values.
first_indexed 2024-03-05T18:10:45Z
format Article
id utm.eprints-7268
institution Universiti Teknologi Malaysia - ePrints
last_indexed 2024-03-05T18:10:45Z
publishDate 2009
publisher Elsevier B.V.
record_format dspace
spelling utm.eprints-72682017-09-13T02:32:45Z http://eprints.utm.my/7268/ A predominant β-CGTase G1 engineered to elucidate the relationship between protein structure and product specificity Goh, Kin Mau Mahadi, Nor Muhammad Hassan, Osman Rahman, Raja Noor Zaliha Raja Abdul Illias, Rosli Md TP Chemical technology Low reaction yields and the high cost of obtaining a single type of pure CD make γ-CD costly. Using rational design and with the aid of 3D modeling structures, recombinant CGTase from Bacillus sp. G1 was molecularly engineered with the aim of producing a higher percentage of γ-CD. A single mutation at subsite -3, denoted H43T, was found to increase γ-CD production from 10% to approximately 39% using tapioca starch. This novel increment was probably the result of reduced steric hindrance to the formation of γ-CD because of the shortened side chain together with the shortened loop at positions 86-89, at substrate-binding subsite -3. A mutation (Tyr188 → Trp) and a deletion at loop 139-144 showed little effect on product specificity; however, mutagenesis at these sites affected cyclization, coupling and hydrolysis activities as well as the kinetic properties of the mutant CGTase. Based on rational design, three further mutations of the mutant H43T (denoted H43T/Δ(139-144)/S134T/A137V/L138D/V139I, H43T/S85G and H43T/Y87F) were constructed and produced γ-CD with yields of 20%, 20% and 39%, respectively. The mutant H43T/Δ(139-144)/S134T/A137V/L138D/V139I had very low cyclization and coupling activities, however their hydrolysis activity was retained. Double mutation (H43T/S85G) caused the enzyme to exhibit higher starch hydrolysis activity, approximately 26 times higher than the native CGTase G1. Although the mutants H43T and H43T/Y87F could produce the same percentage (39%) of γ-CD, the latter was more efficient as the total amount of CD produced was higher based on the Vmax and kcat values. Elsevier B.V. 2009-05 Article PeerReviewed Goh, Kin Mau and Mahadi, Nor Muhammad and Hassan, Osman and Rahman, Raja Noor Zaliha Raja Abdul and Illias, Rosli Md (2009) A predominant β-CGTase G1 engineered to elucidate the relationship between protein structure and product specificity. Journal of Molecular Catalysis B: Enzymatic, 57 (1-4). pp. 270-277. ISSN 1381-1177 http://dx.doi.org/10.1016/j.molcatb.2008.09.016
spellingShingle TP Chemical technology
Goh, Kin Mau
Mahadi, Nor Muhammad
Hassan, Osman
Rahman, Raja Noor Zaliha Raja Abdul
Illias, Rosli Md
A predominant β-CGTase G1 engineered to elucidate the relationship between protein structure and product specificity
title A predominant β-CGTase G1 engineered to elucidate the relationship between protein structure and product specificity
title_full A predominant β-CGTase G1 engineered to elucidate the relationship between protein structure and product specificity
title_fullStr A predominant β-CGTase G1 engineered to elucidate the relationship between protein structure and product specificity
title_full_unstemmed A predominant β-CGTase G1 engineered to elucidate the relationship between protein structure and product specificity
title_short A predominant β-CGTase G1 engineered to elucidate the relationship between protein structure and product specificity
title_sort predominant i² cgtase g1 engineered to elucidate the relationship between protein structure and product specificity
topic TP Chemical technology
work_keys_str_mv AT gohkinmau apredominanti2cgtaseg1engineeredtoelucidatetherelationshipbetweenproteinstructureandproductspecificity
AT mahadinormuhammad apredominanti2cgtaseg1engineeredtoelucidatetherelationshipbetweenproteinstructureandproductspecificity
AT hassanosman apredominanti2cgtaseg1engineeredtoelucidatetherelationshipbetweenproteinstructureandproductspecificity
AT rahmanrajanoorzaliharajaabdul apredominanti2cgtaseg1engineeredtoelucidatetherelationshipbetweenproteinstructureandproductspecificity
AT illiasroslimd apredominanti2cgtaseg1engineeredtoelucidatetherelationshipbetweenproteinstructureandproductspecificity
AT gohkinmau predominanti2cgtaseg1engineeredtoelucidatetherelationshipbetweenproteinstructureandproductspecificity
AT mahadinormuhammad predominanti2cgtaseg1engineeredtoelucidatetherelationshipbetweenproteinstructureandproductspecificity
AT hassanosman predominanti2cgtaseg1engineeredtoelucidatetherelationshipbetweenproteinstructureandproductspecificity
AT rahmanrajanoorzaliharajaabdul predominanti2cgtaseg1engineeredtoelucidatetherelationshipbetweenproteinstructureandproductspecificity
AT illiasroslimd predominanti2cgtaseg1engineeredtoelucidatetherelationshipbetweenproteinstructureandproductspecificity