Article Per Year (5 Year)
p-Index From 2021 - 2026
1.037
P-Index
This Author published in this journals
All Journal HAYATI Journal of Biosciences Makara Journal of Science Jurnal Bioteknologi & Biosains Indonesia
NIKNIK NURHAYATI
Center for Bioindustrial Technology, Laboratorium of Bioindustrial Technology, LAPTIAB BPPT Puspiptek -Serpong
Agriculture, Biological Sciences & Forestry Biochemistry, Genetics & Molecular Biology Earth & Planetary Sciences

Published : 5 Documents Claim Missing Document
Claim Missing Document
Check
Articles

Found 2 Documents
Search
Journal : HAYATI Journal of Biosciences

 1 
Sequence-Structure Based Comparison of Structurally Homologous Thermophilic and Mesophilic Polyethylene Terephthalate (PET) Hydrolases Hasan, Khomaini; Ulfah, Maria; Nurhayati, Niknik; Sabbathini, Gabriela Christy; Wulandari, Sri Rezeki; Putra, I Gede Eka Perdana; Helianti, Is
HAYATI Journal of Biosciences Vol. 31 No. 2 (2024): March 2024
Publisher : Bogor Agricultural University, Indonesia

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.4308/hjb.31.2.348-356

Abstract

Protein structure has a direct impact on thermostability. Deviations in the primary sequence can affect structural changes, leading to alterations in thermostability properties. However, the molecular basis of protein thermostability is unspecified; thus, elucidation of key factors that role particular protein thermostability is required when engineering proteins to be thermostable. To address this challenge, the amino acid composition, hydrophobicity/hydrophilicity ratio, cysteine bridges, and intrinsic features of two structurally homologous but different thermostability, poly(ethylene terephthalate) hydrolase (PETase) were compared. According to the findings, thermostable and thermolabile PETases have similar folds, compactness, and disulfide bridges. Interestingly, an abundance gap of aromaticity, hydrophobic cluster area, polar amino acid and hydrogen bond network compositions demonstrated dominant trends of variations for both PET hydrolases, indicating a pivotal role of these features in the thermostability of PET hydrolase. Furthermore, increased hydrophobic amino acid frequency in the inner surface of thermostable proteins contributed significantly to thermostability by forming more internal hydrophobic interactions and a less hydrophobic patch. There are no consistent trends in insertions and deletions between both PETases. Taken together, these observations demonstrate that hydrophobicity and hydrogen bond networks are essential factors in thermostability of thermostable PETase.
A Comparative Study of Penicillin G Acylase Expression in Two Escherichia coli Strains: BL21 (DE3) and Arctic Express Cendana, Kartika Sari; Wulandari, Sri Rezeki; Sabbathini, Gabriela Christy; Ulfah, Maria; Achnafani, Dini; Abinawanto; Aniqah, Sunni Sofiah; Helianti, Is; Nurhayati, Niknik
HAYATI Journal of Biosciences Vol. 33 No. 3 (2026): May 2026
Publisher : Bogor Agricultural University, Indonesia

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.4308/hjb.33.3.596-604

Abstract

The growing demand for semisynthetic beta-lactams has directed attention towards enzymes, specifically Penicillin G Acylases (PGAs), for their potential in synthesizing these antibiotics. This study delves into the expression of Achromobacter xylosoxidans PGA (AxPGA) in Escherichia coli, with a focus on enhancing the yield of active PGA, often constrained by a complex maturation process. The optimization of PGA expression included variations in IPTG concentration and the addition of CaCl2. Furthermore, the study compared PGA expression in E. coli BL21 (DE3) with that in E. coli Arctic Express (DE3), capable of co-expressing chaperones (chaperonin Cpn60 and Cpn10). Induction with 0.5 mM IPTG resulted in the highest hydrolytic activity in both strains, with Arctic Express (AE) exhibiting significantly higher activity due to improved folding facilitated by cold-adapted chaperonins. Alongside optimal IPTG induction, the addition of 10 mM CaCl2 in the culture media significantly increased PGA activity in both strains, highlighting that Ca2+ supplementation is an effective strategy to enhance the yield of functional PGA. Subcellular fractionation demonstrates that the periplasmic fraction yielded higher volumetric and specific activities compared to the cytoplasmic fractions in both E. coli strains, highlighting the importance of periplasmic processing for PGA maturation. This suggests that extracting the periplasmic fraction is an effective strategy for recovering active PGA while avoiding or reducing contamination either from co-expressed cytoplasmic chaperones or other intracellular proteins. These findings emphasize that induction strategy, ionic stabilization, and host strain selection play synergistic roles in increasing active recombinant PGA expression.
Co-Authors Abinawanto Abinawanto Abinawanto Achnafani, Dini Ahmad Wibisana, Ahmad Aniqah, Sunni Sofiah Cendana, Kartika Sari Feronika Heppy Sriherfyna I Gede Eka Perdana Putra, I Gede Eka Perdana IS HELIANTI Kharis Yohan Abidin, Kharis Yohan KHOMAINI HASAN Maria Ulfah Masdalifah, Masdalifah NANDYAWATI, DEWI Nataniel, Jocelyn Sabbathini , Gabriela Christy Sabbathini, Gabriela Christy Wulandari, Sri Rezeki