• Journal of Life Science
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• v.30 no.3
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• pp.304-312
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• 2020

Agarase can be used in the field of basic science, as well as for production of agar-derived high-functional oligosaccharides and bioenergy production using algae. In 2012, we summarized the classification, origin, production, and applications of agar. In this paper, we briefly review the literature on the recombinant expression of agarases from 2012 to the present. Agarase genes originated from 19 genera, including Agarivorans, Flammeovirga, Pseudoalteromonas, Gayadomonas, Catenovulum, Microbulbifer, Cellulophaga, Saccharophagus, Simiduia, and Vibrio. Of the 47 recombinant agarases, there were only two α-agarases, while the rest were β-agarases. All α-agarases produced agarotetraose, while β-agarases yielded many neoagarooligosaccharides ranging from neoagarobiose to neoagarododecaose. The optimum temperature ranged between 25 and 60℃, and the optimum pH ranged from 3.0 to 8.5. There were 14 agarases with an optimum temperature of 50℃ or higher, where agar is in sol state after melting. Artificial mutations, including manipulation of carbohydrate-binding modules (CBM), increased thermostability and simultaneously raised the optimum temperature and activity. Many hosts and secretion signals or riboswitches have been used for recombinant expression. In addition to gene recombination based on the amino acid sequence after agarase purification, recombinant expression of the putative agarase genes after genome sequencing and metagenome-derived agarases have been studied. This study is expected to be actively used in the application fields of agarase and agarase itself.

• Journal of The Korean Society of Inherited Metabolic disease
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• v.17 no.2
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• pp.69-76
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• 2017

Citrin deficiency is an autosomal recessive disorder caused by mutations in the SLC25A13 gene on chromosome 7q21.3, and a type of urea cycle disorder that causes hyperammonemia. Although neonatal intrahepatic cholestasis and adult-onset type II citrullinemia, a type of citrin deficiency, have been described well in many articles for several decades, failure to thrive and dyslipidemia caused by citrin deficiency (FTTDCD), the other type of citrin deficiency, has been only identified recently. There was previously no case report about FTTDCD in Korea. Patients with FTTDCD could present with loss of appetite, fatigue, failure to thrive, hypoglycemia, hypercitrullinemia, dyslipidemia, and an increased lactate/pyruvate ratio. Routine evaluation may not reveal the cause of hypoglycemia caused by citrin deficiency. We recently had a case that presented with recurrent hypoglycemia in a 30-month-old boy. Chemistry profiling, urine organic acid analysis, plasma acylcarnitine analysis, and hormone studies indicated values within the normal range or non-specific findings. Mutation analysis to identify the cause of hypoglycemia identified the subject as a compound heterozygote carrying each of the c.852_855del ($p.Met285Profs^*2$), and c.1177+1G>A mutant alleles. We report here on this unusual case of citrin deficiency presenting with FTTDCD for the first time in Korea.

• Journal of the korean academy of Pediatric Dentistry
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• v.34 no.3
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• pp.468-472
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• 2007

The Wiskott-Aldrich Syndrome (WAS) is an inherited immunodeficiency caused by a variety of mutations in the gene encoding the WAS protein (WASp). First described in 1937 by Wiskott, the incidence of WAS has so far been estimated at 4 in 106 live births. The Wiskott-Aldrich Syndrome is an X-linked condition characterized by 1) an increased tendency to bleed caused by a reduced number of platelets, 2) recurrent bacterial, viral and fungal infections, and 3) eczema of the skin. The purpose of this report is to present cases highlighting the clinical features of the syndrome and the required considerations in the treatment of patients. The report consists of two particular cases: a 2-year-11-month-old boy seen for a routine oral examination prior to his bone marrow transplantation and a 2-year-6-month-old boy with herpes gingivostomatitis and teeth discoloration.

• Journal of The Korean Society of Inherited Metabolic disease
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• v.20 no.1
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• pp.1-13
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• 2020

Purpose: Gaucher disease (GD), which is the most prevalent lysosomal storage disorder worldwide, is caused by mutations in the glucocerebrosidase gene (GBA). GD is divided into three clinical subtypes based on the appearance of neurological symptoms. Type 1 GD is a chronic non-neuronopathic disease, and types 2 and 3 are acute neuronopathic and chronic neuronopathic forms, respectively. Neuronopathic GD types 2 and 3 are characterized by increased levels of glucosylceramide (GlcCer) and glucosylsphingosine (GlcSph) in the brain, leading to massive loss of neurons. Methods: DNA damage and subsequent apoptosis of H4 cells were observed following neuroglioma H4 cell culture with GlcCer or GlcSph. Neuronal cell apoptosis was more prominent upon treatment with GlcSph. Results: When H4 cells were treated with GlcSph in the presence of tubacin, a histone deacetylase 6 inhibitor (HDAC6i), attenuation of both DNA damage and a reduction in the protein expression levels of GlcSph-induced apoptosis-associated factors were observed. Conclusion: These findings indicated that GlcSph played a prominent role in the pathogenesis of neuronopathic GD by inducing apoptosis, and that HDAC6i could be considered a therapeutic candidate for the treatment of neuronopathic GD.

• Molecules and Cells
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• v.25 no.1
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• pp.55-63
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• 2008

Amyotrophic lateral sclerosis (ALS) is a progressive neurodegenerative disorder characterized by the selective death of motor neurons. Mutations in the SOD1 gene are responsible for a familial form of ALS (FALS). Although many studies suggest that mutant SOD1 proteins are cytotoxic, the mechanism is not fully understood. To investigate the role of mutant SOD1 in FALS, human SOD1 genes were fused with a PEP-1 peptide in a bacterial expression vector to produce in-frame PEP-1-SOD fusion proteins (wild type and mutants). The expressed and purified PEP-1-SOD fusion proteins were efficiently transduced into neuronal cells. Neurones harboring the A4V, G93A, G85R, and D90A mutants of PEP-1-SOD were more vulnerable to oxidative stress induced by paraquat than those harboring wild-type proteins. Moreover, neurones harboring the mutant SOD proteins had lower heat shock protein (Hsp) expression levels than those harboring wild-type SOD. The effects of the transduced SOD1 fusion proteins may provide an explanation for the association of SOD1 with FALS, and Hsps could be candidate agents for the treatment of ALS.

• Journal of Animal Science and Technology
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• v.46 no.1
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• pp.1-6
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• 2004

This study was conducted to investigate novel genetic variations of MCIR^*3 allele. In general, white spotting or white belt on a black backgroud in pigs is determined by the E$^p$ allele at the MCIR/Extention locus. E$^p$ shares a frameshift mutation with the E$^{D2}$ allele for dominant black color. An oligonucleotide primer set was designed to amplify complete coding sequence of the porcine MCIR gene. The MCIR coding sequences obtained from five breeds those were Landrace(white). Yorkshire(white), Hampshire(belt), Berkshire(spot) and Jeju native black pigs(black), were used for this study. A multiple sequence alignment of the MCIR coding region using Clustal W was performed. The total length of the MCIR coding sequence ranged from 963 to 966 base pairs(bp) among the selected breeds. The sequence analysis of the complete coding region of MCIR was revealed that Hampshire and Jeju native black pig have 3 cytosines deletion and Birkshire has 2 cytosines deletion at codon 23(nt68) in Extention loci. Besides the finding, there were three different missense mutations and a frameshift mutation in the MCIR coding region.

• Korean Journal of Veterinary Research
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• v.40 no.3
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• pp.533-541
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• 2000

Biochemical and genetic analysis were carried out to investigate the potential recovery of pathogenecity or related mutations of Brucella abortus RB51 vaccine strains. RB51 strains were recovered from commercial vaccines, including related seed stocks from private companies in Republic of Korea, strain from USA, a reference strain from C university and a field isolate (Daehungjin) from aborted dairy cow after RB51 vaccination were compared with two identified virulent wild strains (S2308 and a field strain isolated from dairy cow in Korea) at the same conditions. All the strains examined, except identified pathogenic strains, revealed the identical characteristics to the original RB51 in biochemical properties, antigen and bacteriophage typing. Outer membrane protein (OMP) profiles from strains of RB51 showed the same patterns with standard RB51 in SDS-PAGE. In addition, Western blotting with the brucella specific monoclonal antibody also indicated that all the vaccine strains were completely deficient in their LPS compared to the pathogenic Br abortus strains. The differences in DNA structures among strains were also possible to detect after PCR. All vaccine strains, except S19, S1119-3, S1075, S544 and Br suis, were amplified a 178bp DNA fragment of eri-gene, and 364bp of IS711 elements. In contrast, 498bp DNA product was only found with Br abortus. Overall evidences in the present study confirmed that the RB51 strains for vaccine production in Korea did not originated from the phenomena of possible recovery of pathogenicity or related to any potential mutation event at all.

• Clinical and Experimental Reproductive Medicine
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• v.29 no.3
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• pp.215-222
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• 2002

Objective : Previous studies have suggested that hyperhomocysteinemia and methylenetetrahydrofolate reductase (MTHFR C677T) mutations are associated with increased risk of recurrent spontaneous abortion (RSA). Recently, a second site polymorphism in MTHFR, 1298A-->C, which changes a glutamic acid into an alanine residue, was shown to be associated with a decreased enzyme activity. We tested whether the variant alleles of MTHFR C677T and A1298C are risk factor (biomarker) for RSA. Materials and Methods: We analyzed DNA from a case-control study in the Korean DNA was extracted from blood samples of 118 patients with RSA and 123 healthy fertile patients as the controls. MTHFR variant alleles were determined by a PCR-restriction fragment length polymorphism assay. Results: We found no evidence for an association between 677TT genotype and risk of RSA (OR=1.95, 95% CI=$0.84{\sim}4.50$, p=0.12). However, the MTHFR 1298AC (OR=0.36, 95% CI=$0.20{\sim}0.63$, p=0.0004) and 1298AC+CC (OR=0.35, 95% CI=$0.20{\sim}0.61$, p=0.0002) genotypes were lower among 118 RSA cases compared with 123 controls, conferring a 2.8-fold decrease in risk of RSA, respectively. Moreover, the combined genotypes of MTHFR 677CC/1298AC (OR=0.30, 95% CI=$0.10{\sim}0.88$, p=0.029) and 677CT/1298AC (OR=0.77, 95% CI=$0.60{\sim}0.99$, p=0.043) also showed significantly lower risk than those with MTHFR 677CC/1298AA type. Conclusion: MTHFR 1298AC, MTHFR 677CC/1298AC and 677CT/1298AC genotypes may represent genetic markers for the protection of RSA at least in Korean women.

• Journal of Microbiology and Biotechnology
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• v.28 no.11
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• pp.1916-1927
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• 2018

Corynebacterium glutamicum is an excellent platform for the production of amino acids, and is widely used in the fermentation industry. Most industrial strains are traditionally obtained by repeated processes of random mutation and selection, but the genotype of these strains is often unclear owing to the absence of genomic information. As such, it is difficult to improve the growth and amino acid production of these strains via metabolic engineering. In this study, we generated a complete genome map of an industrial L-valine-producing strain, C. glutamicum XV. In order to establish the relationship between genotypes and physiological characteristics, a comparative genomic analysis was performed to explore the core genome, structural variations, and gene mutations referring to an industrial L-leucine-producing strain, C. glutamicum CP, and the widely used C. glutamicum ATCC 13032. The results indicate that a 36,349 bp repeat sequence in the CP genome contained an additional copy each of lrp and brnFE genes, which benefited the export of L-leucine. However, in XV, the kgd and panB genes were disrupted by nucleotide insertion, which increase the availability of precursors to synthesize L-valine. Moreover, the specific amino acid substitutions in key enzymes increased their activities. Additionally, a novel strategy is proposed to remodel central carbon metabolism and reduce pyruvate consumption without having a negative impact on cell growth by introducing the CP-derived mutant $H^+$/citrate symporter. These results further our understanding regarding the metabolic networks in these strains and help to elucidate the influence of different genotypes on these processes.

• Biomedical Science Letters
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• v.5 no.1
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• pp.17-26
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• 1999

To evaluate the spreading possibilities of the marRAB mutation of E. coli Mar mutant among gram-negative bacilli, chromosomal marRAB mutations of Mar mutants were transduced by $\lambda$placMu9 into pUC19 (Lac$^{+}$, Ap$^{r}$) cloning site in another strains of E. coli or onto the chrmosome of S. typhimurium and P. aeruginosa, selected for transduction by Mar phenotype, Lac$^{-}$, or Ap$^{r}$, and tested for their antimicrobial resistance with or without addition of salicylate (SAL). Compared with wild type strains of JM109, NM522, harboring pUC19 or not, respectively, all strains of JM109 or NM522 carrying pUC19::marRAB mutation showed higher levels of antimicrobial resistance and SAL induction of Mar phenotype than those of wild type. However, in contrast to the original Mar mutants, there were some tendencies of decreased antimicrobial resistance of JM109 or NM522 harboring pUC19::marRAB mutation with SAL induction against chlorarnphenicol (Cm) and tetracycline (Tc), or Tc and ciprofloxacin (Cp), respectively. Almost the same results, as shown as the cases of E. coli JM109 or NM522, were obtained from all transductants of S. typhimurium and P. aeruginosa, except Cp, against which increased antimicrobial resistance with SAL induction was shown. This study, employed the methods of transformation or transduction among intercellular gene transfer methods between gram-negative bacteria, shows the evidences that suggest indirectly the spreading possibilities of marRAB mutation among gram-negative bacilli.