• Restorative Dentistry and Endodontics
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• 제46권2호
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• pp.25.1-25.12
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• 2021

Objectives: This study used micro-computed tomography (µCT) to compare voids and interfaces in single-cone obturation among AH Plus, EndoSequence BC, and prototype surface pre-reacted glass ionomer (S-PRG) sealers and to determine the percentage of sealer contact at the dentin and gutta-percha (GP) interfaces. Materials and Methods: Fifteen single-rooted human teeth were shaped using ProTaper NEXT size X5 rotary files using 2.5% NaOCl irrigation. Roots were obturated with a single-cone ProTaper NEXT GP point X5 with AH Plus, EndoSequence BC, or prototype S-PRG sealer (n = 5/group). Results: The volumes of GP, sealer, and voids were measured in the region of 0-2, 2-4, 4-6, and 6-8 mm from the apex, using image analysis of sagittal µCT scans. GP volume percentages were: AH Plus (75.5%), EndoSequence BC (87.3%), and prototype S-PRG (94.4%). Sealer volume percentages were less: AH Plus (14.3%), EndoSequence BC (6.8%), and prototype S-PRG (4.6%). Void percentages were AH Plus (10.1%), EndoSequence BC (5.9%), and prototype S-PRG (1.0%). Dentin-sealer contact ratios of AH Plus, EndoSequence BC, and prototype S-PRG groups were 82.4% ± 6.8%, 71.6% ± 25.3%, and 70.2% ± 9.4%, respectively. GP-sealer contact ratios of AH Plus, EndoSequence BC, and prototype S-PRG groups were 65.6% ± 29.1%, 80.7% ± 25.8%, and 87.0% ± 8.6%, respectively. Conclusions: Prototype S-PRG sealer created a low-void obturation, similar to EndoSequence BC sealer with similar dentin-sealer contact (> 70%) and GP-sealer contact (> 80%). Prototype S-PRG sealer presented comparable filling quality to EndoSequence BC sealer.

• 미생물학회지
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• 제42권1호
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• pp.67-72
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• 2006

클로닝된 Bacillus circulans ATCC21367 유래 cellulolytic xylanase 유전자(bglBC2)의 염기서열을 결정 분석하였다. 본 유전자는 1,224 bp의 407개 아미노산을 암호하는 open reading frame (ORF)으로 구성되어 있었으며 염기서열로부터 산출된 유전자의 분자량은 45 kDa으로 효소의 SDS-PAGE로부터 측정된 분자량과 일치하였다. ATG 개시 코돈의 9bp 위쪽에 Shine-Dalgarno (SD) 서열로 추정되는 5'-AAAGGAG-3' 서열이 확인되었고 그 상단에 promoter로 추정되는 -35 서열(TTTACA)과 -10 서열(TATACT)이 위치하고 있었으며, 이는 B. subtilis promoter consensus sequence와 유사하였다. 한편, 이 효소의 아미노산 서열은 이미 보고된 B. circulans KSM-N257의 alkaline $endo-\beta-1,4-glucanase$와는 97%, B. circulans WL-12의 $endo-\beta-1,3-1,4-glucanase$와는 75%, Bacillus sp. KSM-330의 $endo-\beta-1,4-glucanase$ (cellulase)와는 45%의 유사성을 나타내었다. 또한 bglBCS 염기서 열의 정보를 GenBank에 등록하였으며 등록번호는 Ar269256이다.

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2000년도 추계학술발표대회 및 bio-venture fair
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• pp.655-659
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• 2000

토양에서 분리한 endo-inulinase 생산 균주인 Xanthomonas oryzae #5로 부터 11.5kb의 endo-inulinase 유전자를 포함하는 재조합 plasmid를 함유한 형질 전환주를 분리하였다. 11.5kb의 단편으로부터 8.6kb, 4.1kb의 단편을 포함한 pDI 2, pDI4 재조합 plasmid를 제작하여 활성을 확인한 결과 endo-inuliase 활성을 나타내었으며, 재조합 plasmid pDI 2를 이용하여 DNA sequence를 한 결과 endo-inulinase 유전자는 1,333개의 아미노산으로 구성된 ORF를 가지고 있었다. 또한 B. circulans MCI-2554의 CFTase와 아미노산 배열에 있어은 약 72%의 높은 homology를 나타냈었으며, 다른 fructan hydrolases, inulinase, levanase와의 아미노산 비교로부터 ${\beta}-fructouranosidase$ motif를 포함한 6개의 유사부위를 확인하였다.

• Journal of Microbiology and Biotechnology
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• 제5권3호
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• pp.117-124
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• 1995

A gene (xynA) encoding the endo-xylanase (E.C.3.2.1.8) from Bacillus stearothermophilus was cloned in E. coli, and its complete nucleotide sequence was determined. The xynA gene consists of a 636 base pairs open reading frame coding for a protein of 212 amino acids with a deduced molecular weight of 23, 283 Da. A putative signal sequence of 27 amino acid residues shows the features comparable with the Bacillus signal sequences; namely, the signal contains a positively charged region close to the N-terminus followed by a long hydrophobic string. The coding sequence is preceded by a possible ribosome binding site with a free energy value of -16.6 kcal/mol and the transcription initiation signals are located further upstream. The translation termination codon (TAA) at the 3 end of the coding sequence is followed by two palindrome sequences, one of which is thought to act as a terminator. The xynA gene has a high GC content, especially in the wobble position of codons (64%). Comparison of the primary protein sequence with those of other xylanases shows a high homology to the xylanases belonging to family G.

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2000년도 추계학술발표대회 및 bio-venture fair
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• pp.202-205
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• 2000

A gene coding $endo-{\beta}$,-1, 4 glucanase from Actinomyces sp. KNG40 and phytase from Hansenula polymorpha were cloned into Esherichia coli JM101 by using E. coli/Lactobacillus shuttle vector pNZ3004 and pNZ123. The plasmid p3PS(1-4) and p123(1-4) have slpA promoter and slpA signal sequence. So, I constructed expression vectors, p3PS(1-4)Endo, phy and p123(1-4)Endo, phy. These constructed vector was transformed in target host Lactobacillus gasseri and reutri. These transformed host expressed endoglucanase and phytase as extracellular fraction. In the enzyme activity of the same vector, host L, gasseri was higher activity than L. reuteri. This indicates that L. gasseri recongnize promoter and signal sequence very well.

• BMB Reports
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• 제40권6호
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• pp.1095-1099
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• 2007

Endonuclease G (EndoG) is a mitochondrial non-specific nuclease that is highly conserved among the eukaryotes. Although the precise role of EndoG in mitochondria is not yet known, the enzyme is released from the mitochondria and digests nuclear DNA during apoptosis in mammalian cells. Schizosaccharomyces pombe has an EndoG homolog Pnu1p (previously named SpNuc1) that is produced as a precursor protein with a mitochondrial targeting sequence. During the sorting into mitochondria the signal sequence is cleaved to yield the functionally active endonuclease. From the analogy to EndoG, active extramitochondrial Pnu1p may trigger cell killing by degrading nuclear DNA. Here, we tested this possibility by expressing a truncated Pnu1p lacking the signal sequence in the extramitochondrial region of pnu1-deleted cells. The truncated Pnu1p was localized in the cytosol and nuclei of yeast cells. And ectopic expression of active Pnu1p led to cell death with fragmentation of nuclear DNA. This suggests that the Pnu1p is possibly involved in a certain type of yeast cell death via DNA fragmentation. Although expression of human Bak in S. pombe was lethal, Pnu1p nuclease is not necessary for hBak-induced cell death.

• Restorative Dentistry and Endodontics
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• 제42권1호
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• pp.19-26
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• 2017

Objectives: Recently, bioceramic sealers like EndoSequence BC Sealer (BC Sealer) have been introduced and are being used in endodontic practice. However, this sealer has limited research related to its retreatability. Hence, the aim of this study was to evaluate the retreatability of two sealers, BC Sealer as compared with AH Plus using micro-computed tomographic (micro-CT) analysis. Materials and Methods: Fifty-six extracted human maxillary incisors were instrumented and randomly divided into 4 groups of 14 teeth: 1A, gutta-percha, AH Plus retreated with chloroform; 1B, gutta-percha, AH Plus retreated without chloroform; 2A, gutta-percha, EndoSequence BC Sealer retreated with chloroform; 2B, gutta-percha, EndoSequence BC Sealer retreated without chloroform. Micro-CT scans were taken before and after obturation and retreatment and analyzed for the volume of residual material. The specimens were longitudinally sectioned and digitized images were taken with the dental operating microscope. Data was analyzed using an ANOVA and a post-hoc Tukey test. Fisher exact tests were performed to analyze the ability to regain patency. Results: There was significantly less residual root canal filling material in the AH Plus groups retreated with chloroform as compared to the others. The BC Sealer samples retreated with chloroform had better results than those retreated without chloroform. Furthermore, patency could be re-established in only 14% of teeth in the BC Sealer without chloroform group. Conclusion: The results of this study demonstrate that the BC Sealer group had significantly more residual filling material than the AH Plus group regardless of whether or not both sealers were retreated with chloroform.

• Journal of Applied Biological Chemistry
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• 제42권2호
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• pp.71-74
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• 1999

The crude enzyme prepared from the culture supernantant of Arthrobacter sp. S37 was purified by Phenyl Toyopearl column chromatography. Six endo-inulinases were detected by activity staining on native PAGE and named Inu I to Inu VI. Endo-inulinase were further purified by DEAE cellulose column chromatography and band slicing. Inu II~VI produced mainly inulotriose (F3) and inulotetraose (F4) as well as a small amount of inulobiose (F2) and fructose in contrast to Inu I producing F3, F4 and F5 from inulin. The N-terminal amino acid sequence of native and six CNBr-cleaved fragment of Inu VI were determined. No homology was found in amino acid sequences between Inu VI and other fructan hydrolase including invertase reported.

• Journal of the Korean Wood Science and Technology
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• 제25권2호
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• pp.100-109
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• 1997

The objectives of this study was to decrease pollutions of bleaching effluent and was to enhanced brightness of non-chlorine bleached pulps by xylanase treatments. Xylanase cloned Esherichacoli(E. coli) capable of each of endo, exo-xylanase and acetyl-esterase were obtained from Bacillus stearothermophillus. These xylanase was maintained high activity in alkali and high temperature. Especially endo-xylanase would be more active in $60^{\circ}C$ and pH 11. Xylanase pretreatment(X) of unbleached pulp increased brightness, and decreased the degree of delignification. The degree of increase in brightness of pulp due to xylanase pretreatment was similar to non-enzyme treated pulp, regardless of the amount of enzyme added. Therefore, the addition of xylanase of 2 unit was recommended when considering costs of enzyme. The pulp bleached XO sequence had higher brightness and lower Kappa no, than O bleached pulp, while pulp bleached XP sequence had similar brightness and Kappa no. with P bleached pulp. In XOC/D, XOZ and XOP bleaching sequences, brightness and degree of delignification were improved. The C/D and Z stage bleached pulp was good effect on rate of raise in brightness and Kappa no., but P stage bleached pulp had similar level in non-enzyme treated bleaching sequence.

• BMB Reports
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• 제31권2호
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• pp.123-129
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• 1998

Foreign proteins, $endo-{\beta}-1,4-glucanase$ of Bacillus subtilis, preS1+S2 region of hepatitis B virus large surface antigen, human ${\beta}_2-adrenergic$ receptor ($h{\beta}_{2}AR$), and bovine growth hormone (bGH) were expressed in Saccharomyces cerevisiae and secreted into the medium. These proteins were expressed using the alcohol dehydrogenase I (ADH1) promoter of Saccharomyces cerevisiae and secreted by signal sequence of the 97 K killer toxin gene of doublestranded linear DNA plasmid (pGKL1) of S. cerevisiae. All these proteins underwent severe modifications; in particular, N-glycosylation in the case of $endo-{\beta}-1,4-glucanase$, $h{\beta}_2AR$, and preS1+S2. Seventy four percent of the expressed $endo-{\beta}-1,4-glucanase$ was secreted into the culture medium. Highly modified proteins were detected in the culture medium and in the cell. Expressed $h{\beta}_2AR$, which has seven transmembrane domains, remained in the cell. The degrees of secretion and modification and the states of proteins in the culture medium and in the cell were quite different. These results indicated that the nature of the protein has a critical role in its secretion and modifications.