• Fisheries and Aquatic Sciences
• /
• 제25권1호
• /
• pp.1-11
• /
• 2022

Catfish is one of the most important freshwater fish farming commodities in Indonesia. Higher catfish production can be achieved by cultivating transgenic catfish carrying the growth hormone (GH) gene of African catfish (Clarias gariepinus GH, CgGH). This research focuses on analysis of the presence of the CgGH gene in transgenic G₁, G₂, and G₃ mutiara catfish broodstock, as an indication of stable CgGH inheritance. CgGH gene was isolated using the RNeasy mini kit and RT-PCR. RT-PCR revealed amplicons measuring approximately 600 bp in transgenic G₀, G₁, G₂, and G₃ mutiara catfish. The CgGH consensus sequence similarities ranged from 93.76% to 97.06%, with four functional domain sites (somatotropin-1, somatotropin-2, four α-helix, N-glycosylation, four cysteine residues) of fish GH proteins. The functional domains of fish GH proteins are conserved in G₁, G₂, and G₃ and indicate stable exogenous GH inheritance to produce transgenic catfish strains in each generation.

• BMB Reports
• /
• 제44권10호
• /
• pp.674-679
• /
• 2011

Bacillus sphaericus produces mosquito-larvicidal binary toxin composed of BinA and BinB. While BinB is expected to bind to a specific receptor on the cell membrane, BinA interacts to BinB or BinB receptor complex and translocates into the cytosol to exert its activity via unknown mechanism. To investigate functional roles of aromatic cluster in BinA, amino acids at positions Y213, Y214, Y215, W222 and W226 were substituted by leucine. All mutant proteins were highly produced and their secondary structures were not affected by these substitutions. All mutants are able to insert into lipid monolayers as observed by Langmuir-Blodgett trough and could permeabilize the liposomes in a similar manner as the wild type. However, mosquito-larvicidal activity was abolished for W222L and W226L mutants suggesting that tryptophan residues at both positions play an important role in the toxicity of BinA, possibly involved in the cytopathological process after toxin entry into the cells.

• BMB Reports
• /
• 제42권4호
• /
• pp.206-211
• /
• 2009

Proopiomelanocortin (POMC) plays an essential role in the stress response of the hypothalamic-pituitary-adrenal axis, and is the precursor of biologically active peptides such as adrenocorticotropin (ACTH), $\alpha$-melanocyte-stimulating hormone ($\alpha$-MSH), $\beta$-melanocyte-stimulation hormone ($\beta$-MSH) and $\beta$-endorphin. We have synthesized two different forms of POMC cDNA clones, POMC-I and POMC-II, from a pituitary cDNA library for Paralichthys olivaceus, or Japanese flounder. jfPOMC-I cDNA consists of 954bp and encodes a polypeptide of 216 amino acid residues, whereas jfPOMC-II consists of 971bp which encode a polypeptide of 194 amino acid residues. The high levels of jfPOMC-I and -II mRNAs detected in the pituitary tissue and moderate levels detected in the brain tissue plus our quantitative RT-PCR analysis, which showed there to be no significant difference between the levels of jfPOMC-I and -II mRNAs, indicate that there may be no functional separation between these two mRNAs in the flounder.

• BMB Reports
• /
• 제45권6호
• /
• pp.360-364
• /
• 2012

Uptake of circulating glucose into the cells happens via the insulin-mediated signalling pathway, which translocates the glucose transporter 4 (GLUT4) vesicles from the intracellular compartment to the plasma membrane. Rab GTPases are involved in this vesicle trafficking, where Rab GTPases-activating proteins (RabGAP) enhance the GTP to GDP hydrolysis. TBC1D4 (AS160) and TBC1D1 are functional RabGAPs in the adipocytes and the skeletonal myocytes, respectively. These proteins contain two phosphotyrosine-binding domains (PTBs) at the amino-terminus of the catalytic RabGAP domain. The second PTB has been shown to interact with the cytoplasmic region of the insulin-regulated aminopeptidase (IRAP) of the GLUT4 vesicle. In this study, we quantitatively measured the ${\sim}{\mu}M$ affinity ($K_D$) between TBC1D4 PTB and IRAP using isothermal titration calorimetry, and further showed that IRAP residues 1-49 are the major region mediating this interaction. We also demonstrated that the IRAP residues 1-15 are necessary but not sufficient for the PTB interaction.

• 한국잠사곤충학회지
• /
• 제39권1호
• /
• pp.44-55
• /
• 1997

This study was carried out to find out the relationship between qualities and contraction phenomenon of silk fibers by treatment of concentrated neutral salts. The contraction effects of silk fibers showed the critical point on the treatment conditions of concentration, temperature and time, among three kinds of neutral salts such as calcium nitrate, calcium chloride and lithium bromide. But, The silk fibers, pretreated with bromide and/or formaldehyde, did not show the contraction upon treating with calcium nitrate. This indicates that tyrosine and serine can be correlated with the contraction reaction because of coupling these amino acids with bromide and formaldehyde. In conclusion, a mechanism for the contraction of silk fiber with highly concentrated calcium nitrate solution is supposed as follows. At the initial stage of ration, the water was penetrated into the amorphous regions and fibers swollen, therefore, the contraction took place mainly in amorphous regions, which have plenty of functional groups with hydroxyl residues. Then, as the calcium nitrate is penetrated into the microfibril, the gydrogen bonds of tyrosine and serine residues and broken and crystalline regions are more and more influenced by increasing concentration of calcium nitrate solution. Microgibrils of crystalline regions become entangled, contracted to linear direction and rearranged to form new stable hydrogen bonds.

• Journal of Microbiology and Biotechnology
• /
• 제20권2호
• /
• pp.294-300
• /
• 2010

The Iro protein is a member of the HiPIP family with the [$Fe_4S_4$] cluster for electron transfer. Many reports proposed that the conserved aromatic residues might be responsible for the stability of the iron-sulfur cluster in HiPIP. In this study, Tyr10 was found to be a critical residue for the stability of the [$Fe_4S_4$] cluster, according to site-directed mutagenesis results. Tyr10, Phe26, and Phe48 were essential for the stability of the [$Fe_4S_4$] cluster under acidic condition. Trp44 was not involved in the stability of the [$Fe_4S_4$] cluster. Molecular structure modeling for the mutant Tyr10 proteins revealed that the aromatic group of Tyr10 may form a hydrophobic barrier to protect the [$Fe_4S_4$] cluster from solvent.

• Bulletin of the Korean Chemical Society
• /
• 제35권6호
• /
• pp.1769-1776
• /
• 2014

Binding modes of a series of catechol derivatives such as protein tyrosine phosphatase 1B (PTP1B) inhibitors were identified by molecular modeling techniques. Docking, molecular dynamics simulations and free energy calculations were employed to determine the modes of these new inhibitors. Binding free energies were calculated by involving different energy components using the Molecular Mechanics-Poisson-Boltzmann Surface Area and Generalized Born Surface Area methods. Relatively larger binding energies were obtained for the catechol derivatives compared to one of the PTP1B inhibitors already in use. The Molecular Mechanics/Generalized Born Surface Area (MM/GBSA) free energy decomposition analysis indicated that the hydroxyl functional groups and biphenyl ring system had favorable interactions with Met258, Tyr46, Gln262 and Phe182 residues of PTP1B. The results of hydrogen bound analysis indicated that catechol derivatives, in addition to hydrogen bonding interactions, Val49, Ile219, Gln266, Asp181 and amino acid residues of PTP1B are responsible for governing the inhibitor potency of the compounds. The information generated from the present study should be useful for the design of more potent PTP1B inhibitors as anti-diabetic agents.

• BMB Reports
• /
• 제45권4호
• /
• pp.239-241
• /
• 2012

Iron availability is limited in the environment and most bacteria have developed a system to acquire iron from host hemoproteins. Heme oxygenase plays an important role by degrading heme group and releasing the essential nutrient iron. The structure of Bacillus subtilis HmoB was determined to 2.0 ${\AA}$ resolution. B. subtilis HmoB contains a typical antibiotic biosynthesis monooxygenase (ABM) domain that spans from 71 to 146 residues and belongs to the IsdG family heme oxygenases. Comparison of HmoB and IsdG family proteins showed that the C-terminal region of HmoB has similar sequence and structure to IsdG family proteins and contains conserved critical residues for heme degradation. However, HmoB is distinct from other IsdG family proteins in that HmoB is about 60 amino acids longer in the N-terminus and does not form a dimer whereas previously studied IsdG family heme oxygenases form functional homodimers. Interestingly, the structure of monomeric HmoB resembles the dimeric structure of IsdG family proteins. Hence, B. subtilis HmoB is a heme oxygenase with a novel structural feature.

• BMB Reports
• /
• 제43권1호
• /
• pp.23-28
• /
• 2010

Binary toxin consisting of BinA and BinB from Bacillus sphaericus is toxic to mosquito larvae. BinB is responsible for specific binding to the larval gut cell membrane while BinA is crucial for toxicity. To investigate functional role of cysteine in BinB, three cysteine residues at positions 67, 161, and 241 were replaced by alanine or serine. Mutations at these positions did not affect protein production and overall structure of BinB. These cysteine residues are not involved in disulfide bond formation between BinB molecules. Mosquito-larvicidal assays revealed that C67 and C161 are essential for toxicity, whereas C241 is not. Mutations at C67 and C161 resulted in weaker BinA-BinB interaction. The loss of toxicity may be due to the reduction of interactions between BinA and BinB or BinB and its receptor. C67 and C161 could also play a part during conformational changes or internalization of the binary toxin into the target cell.

• Journal of Microbiology and Biotechnology
• /
• 제30권11호
• /
• pp.1739-1749
• /
• 2020

Exopolysaccharide produced by the yeast Papiliotrema flavescens, isolated from wine grape berries of Champagne vineyard, was investigated for both chemical and functional characterization. SECMALLS and colorimetric assay analyses showed that the EPS is a high M_W heteropolymer (2.37 × 10⁶ g/mol) majorily consisting of mannose, glucose, xylose and glucuronic acid as monosaccharide constituents, with two substituents (sulphate and phosphate groups), and a minor protein moiety. Structural enchainment of these carbohydrates based on methylation, GC-MS and NMR analyses revealed a linear main backbone built up of α-(1 → 3)-D-mannopyranosyl residues on which are branched side chains consisting of a single β-D-glucopyranosyluronic acid residue and β-(1 → 2)-xylopyranoses (2-5 residues). Suggestion of some xylopyranose side chains containing a mannose residue at the nonreducing terminal end was also proposed. This is first report on EPSs from the grape P. flavescens yeast with such structural characteristics. Furthermore, investigations for valuating the application performance of these EPS in relation with their structural features were carried out in 8% alcohol experiment solutions. Very exceptional viscosifying and foaming properties were reported by comparison with commercial biopolymers such as Arabic, gellan and xanthan gums. The intrinsic properties of the natural biopolymer from this wild grape-associated P. flavescens yeast make it a potential candidate for use in various biotechnology applications.