• The Journal of Korean Institute of Communications and Information Sciences
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• v.34 no.5B
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• pp.469-479
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• 2009

The GEM frame is used a mean to deliver the variable length user data and consists of the header and the payload in the G-PON system. The HEC field of header protects contents of the header and is used to maintain GEM frame synchronization at the same time. When an LCDG (Loss of GEM Channel Delineation) occurs while receiving frames, the receiver have to discard corrupted frames until acquiring the synchronization again. Accordingly, high-speed synchronization method is required to minimize the frame loss. In this paper, we suggest not only a main state machine but a sub-state machine to reduce the frame loss when undetectable errors occurred in the GEM header. Also, we provide a more efficient and fast parallel structure to detect the starting point of the header. Finally, the proposed method is implemented with the FPGA and verified by the logic analyzer.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.36 no.5B
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• pp.429-436
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• 2011

The G-PON is an efficient solution to implement the FTTH and have GEM frame to accomodate various protocols like Ethernet frames, IP packets, and TDM signals. Above all, the Ethernet is one of the most widely used 2nd layer protocol in the campus, the subscriber access, and the carrier service. So G-PON system has to provide an Ethernet interface with top priority. In this paper, we implement a gigabit Ethernet adapter based on Ethernet over GEM in the ITU-T G.984.3 to accommodate Ethernet protocol in the G-PON TC chip. The adapter maps each Ethernet frame to a single or multiple GEM frames and has several functions including generation of the GEM header, encapsulation of frames and the SAR. In particular, the adapter have converter (LUT) MAC address to port-ID which is a key to identify logical connections though it is not defined in specification but important. We implement the adapter with a FPGA and verify the functions of segmentation and reassembling, MAC address learning, and throughput with the logic analyzer and the Ethernet analyzer.

• Applied Biological Chemistry
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• v.39 no.2
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• pp.112-117
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• 1996

Arginine decarboxylase (ADC) is the first enzyme in one of the two pathways of diamine putrescine biosynthesis in plants. The genes encoding ADC have previously been cloned from Escherichia coli, oat and tomato genome. Two degenerate oligonucleotides (17-mer) corresponding to two conserved regions of ADC were used as primers in polymerase chain reaction of rice (Oryza sativa L.) genomic DNA, and an approximately 1.0 kbp fragment was obtained. This amplified PCR product showed an open reading frame which contains 1,022 bp of nucleotide sequences. This PCR product was cloned into pGEM-originated T vector and the short 500 bp PstI digested fragment was subcloned into pGEM-3zf(+/-) vectors to facilitate sequencing. The nucleotide sequence of this PCR product showed about 74% and 70% identity with the same regions of the oat and tomato ADC cDNA sequences, respectively. The predicted amino acid sequence exhibited 45% and 62% identity with oat and tomato ADC polypeptide fragments, respectively. The sequence similarities of 34%, 47% and 38% were previously reported in oat and E. coli, tomato and oat, and tomato and E. coli ADC amino acids, respectively. Therefore, similarities and identities between rice and oat or tomato are remarkably higher than those others of the previous reports. In the highly conserved regions in both the amino acid sequence and spacing regions among the sequences of these three, rice ADC open reading frame also has the exactly same regions with the striking similarity. RNA blot analysis showed that hnc is expressed as a transcript of approximately 2.5 kbP in the rice seedling leaf tissues.

• Korean Journal of Plant Tissue Culture
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• v.24 no.2
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• pp.93-97
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• 1997

For the molecular genetic study of cold tolerance mechanism in plants, a cDNA encoding fatty acid desaturase (fad3), converting linoleic acid (18:2, $\omega$-6) to linolenic acid (18:3, $\omega$-3), was isolated from $\lambda$ZAPII Arabidopsis thaliana cDNA expression library by plaque hybridization using fad3 cDNA probe derived from Brassica napus. A 1.8 kb-EcoRI fragment from a lambda clone showing a strong positive hybridization signal was subcloned into pGEM7 and analyzed for its nucleotide sequence. From deduced amino acid sequences, the fad3 gene was revealed to have an open reading frame(ORF) consisting of 386 amino acids with a molecular mass of 44,075 Da. The fad3 gene was compared to chloroplast $\omega$-3 fatty acid desaturase (fad7) and endoplasmic reticulum Δ12 fatty acid desaturase (fad2) to show 70% and 58% amino acid sequence homology, respectively, Especially, amino acids of internal (82 to 151) and carboxy terminal (276 to 333) regions were highly conserved, implying their requisite role for enzymatic functioning of fatty acid desaturases. IPTG-induced fad3 cDNA expression in E. coli cells was suggested to be toxic to bacterial growth.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2000.04a
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• pp.129-133
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• 2000

It is reasonable to use the stereo vision and image processing technique to digitize 3D coordinates of grid points and to evaluate surface strains on a sheet metal parts. However this method has its intrinsic problems such as the difficulty in enhancement of bad images inevitable error due to digital image resolution of camera and frame grabber unreliability of strains and thickness evaluated from coarse grid on the corner area with large curvature and the limitation of the area that can be measured at a time. Therefore it is still hard to measure strain distribution over the entire surface of a medium,- or large-sized stamped part at a time even by using an automated strain measurement system. In this study the curvature correction algorithm based on the grid refinement and the geometry assembling algorithm based on the global error minimization (GEM) scheme are suggested. Several applications are presented to show the reliability and efficiency of these algorithms.

• Parasites, Hosts and Diseases
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• v.31 no.3
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• pp.285-292
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• 1993

C. sinensis total RMh was containing large amount of 185 rRNA but little 285 rRNA. The size of the double-stranded cDNA synthesized from poly $(A)^{+}$ mRNA was 0.4-4.2 kb long with tapering unto 9.5 kb. Degenerated oligonucleotides (as 2 sense and 3 antisense Primers) were designed on the conserved regions of the known tropomyosin amino acid sequences. From one out of the PCR amplifications using total CDNA and matrix of primers, a specific gene product, 580 bp in size, was produced. Upon Southern hybridization of the PCR products with Schistosomn mnnsoni tropomyosin (SMTM) CDNA, only one signal appeared at the band of 580 bp product. This 580 bp product was considered to encode C. sinensis tropomyosin (CSTM) and cloned in pGEM-3Zf(-) for DNA sequencing. CSTM cDNA was 575 bp containing one open reading frame of 191 predicted amino acids, which revealed 86.3% homology with SMTM and 51.1% with rrichostronsylur coeubnlormis tropomyosin. CSTM cDNA obtained will serve as a probe in the studies of molecular cloning of CSTM.

• Journal of Microbiology and Biotechnology
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• v.10 no.4
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• pp.559-563
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• 2000

A dextransucrase gene (dsrB742) that expresses a dextransucrase to synthesize mostly ${\alpha}-1{\rightarrow}6$ linked dextran with a low amount (3-5%) of ${\alpha}-1{\rightarrow}3$ branching was cloned and sequenced from Leuconostoc mesenteroides B-742CB. The 6.1-kb PstI fragments were ligated with pGEM-3Zf(-) and transformed into E. coli $DH5{\alpha}$. The recombinant clone (pDSRB742) synthesized dextran on an agar plate containing 2% (w/v) sucrose. The dextran synthesized was hydrolyzed with Penicillium endo-dextranase. The hydrolyzate was composed of glucose, isomaltose, isomaltotriose, and branced pentasaccharide. The nucleotide sequence of dsrB742 showed one open reading frame (ORF) composed of 4,524 bp encoding dextrasnsucrase. The deduced amino acid sequence revealed a calculated molecular mass of 168.6 kDa. It also showed an activity band of 184 kKa on a non-denaturing SDS-PAGE (10%). The amino acid sequence of DSRB742 exhibited a 50% similarity with DSRA from L. mesenteroides B-1299, a 70% similarity with DSRS from L. mesenteroides B-512 (F, FMCM) and a 45-56% similarity with Streptococcal GTFs.

• Journal of Microbiology and Biotechnology
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• v.14 no.3
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• pp.563-569
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• 2004

The DNA sequence of the chitosanase gene (choK) from $\beta$-Proteobacterium KNU3 showed an 1,158-bp open reading frame that encodes a protein of 386 amino acids with a novel 74 signal peptide. The degenerated primers based on the partial deduced amino acid sequences from MALDI- TOF MS analyses yielded the 820 bp of the PCR product. Based on this information, double inverse PCR cloning experiments, which use the two specific sets of PCR primers rather than single set primers, identified the unknown 1.2 kb of the choK gene. Subsequently, a 1.8 kb of full choK gene was cloned from another PCR cloning experiment and it was then subcloned into pGEM T-easy and pUC18 vectors. The recombinant E. coli clone harboring recombinant pUC18 vector produced a clear halo around the colony in the glycol chitosan plates. The recombinant ChoK protein was secreted into medium in a mature form while the intracellular ChoK was produced without signal peptide cleavage. The activity staining of PAGE showed that the recombinant ChoK protein was identical to the chitosanase of wild-type. The comparison of deduced amino acid sequences of choK revealed that there is 92% identity with that of Sphingobacterium multivorum chitosanase. Judging from the conserved module in other bacterial chitosanases, chitosanase of KNU3 strain (ChoK) belongs to the family 80 of glycoside hydrolases.

• Journal of Sericultural and Entomological Science
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• v.49 no.2
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• pp.37-42
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• 2007

Lactoferrin, an ion-binding 80-kDa glycoprotein, has been suggested to have many biologic activities, such as facilitating ion absorption and having antimicrobial and anti-inflammatory effects. Several of these activities are likely to only be facilitated by human lactoferrin because they depend on the binding of human lactoferrin to specific receptor. To produce recombinant human lactoferrin to animal foods using transgenic silkworm, Bombyx mori L, we have cloned and sequenced the cDNA encoding for a human lactoferrin (HLf) from the mRNA in mammary tumor line (GI-101). As a result, the 2.5-kb fragment of HLf gene was cloned with pGEM-T vector and then this fragment was sequenced. In the nucleotide sequence analysis, single open reading frame of the 2,136-bp encoding for a polypeptide of 712 amino acid residues was detected. On the other hand, we constructed a recombinant plasmid(pPT-HLf), containing human lactoferrin gene for germ line transformation of the silkworm using a piggyBac transposon-derived vector. A nonautonomous helper plasmid encodes the piggyBac transposase. Approximately 6.7% of individuals in the G0 silkworms expressed green fluorescent protein (GFP). PCR analyses of GFP-positive silkworms (G0 and G1) revealed that independent insertions occurred frequently. Furthermore, Western blot analysis showed that the recombinant HLf expressed in hemolymph has the same molecular weight (80 kDa) as a native protein. On the basis of these experiments, expression of HLf in next generation of transgenic silkworm is now in process.