• Journal of Microbiology
• /
• v.37 no.3
• /
• pp.168-174
• /
• 1999

Escherichia coli O157 is an important pathogenic organism which causes diarrhea, haemorrhagic colitis, and haemolytic ureamic syndrome (HUS) in human. E. coli O157 KNIH317 was isolated form patients suffering with HUS in Korea. We designed a primer set for cloning shiga-like toxin (slt) gene. The amplified PCR product was used to Southern and colony hybridization as a probe. As a result, we cloned 4.5-kb KpnI fragment containing the slt gene encoding shiga-like toxin from chromosomal DNA of E. coli O157 KNIH317. This recombinant plasmid was named pOVT45. E. coli XL1-Blue harboring pOVT45 showed cytotoxicity in Vero cells. We sequenced the slt gene of this strain. The A-subunit gene of the slt was composed of 960 base pairs with ATG initiation codon and TAA terminationcodon. The B-subunit was composed of 270 base paris with ATG initiation codon and TGA termination codon. Nucleotide sequence comparison of the slt gene exhibited 100%, 98.4%, 93.7%, and 93.7% identity with that of shiga-like toxin type II (sltII) of E. coli bacteriophage 933W, variant slt of E. coli, slt of E. coli, and variant sltII of E. coli, respectively. From these results, it was concluded that the cloned slt gene belongs to SltII family and that the strain used in this study may be a lysogeny of E. coli bcteriphage 933W.

• The Korean Journal of Physiology and Pharmacology
• /
• v.1 no.2
• /
• pp.195-200
• /
• 1997

Water transport in highly-permeable membranes is facilitated by some specialized pathways, which are called aquaporins (AQP). AQP1 (AQP-CHIP) is the first recognized aquaporin identified from red cells and renal proximal tubules. Up until now 4 other aquaporin homologs have been reported. Each aquaporin has its unique tissue distribution and regulatory mechanims. To elucidate molecular mechanisms for their transcription regulation and tissue-specific expression isolation of aquaporin genes is required. To clone promoters of the AQP family mouse genomic library was screened by the 1st exon-specific probe of AQP4, and 5 different plaques were positively hybridized. Phage DNAs were purified and characterized by restriction mapping and sequencing. One of them is the mouse AQP-CD gene. The gene was consisted of 4 exons and the exon-intron boundaries of mouse AQP-CD gene were identified at identical positions in other related genes. The 5'-flanking region of AQP-CD gene contains one classic TATA box, a GATA consensus sequence, an E-box and a cyclic AMP-responsive element. The cloning of the mouse AQP-CD gene, of which product is expressed in the collecting duct and is responsible for antidiuresis by vasopressin, will contribute to understand the molecular mechanisms of tissue-specific expression and regulation of AQP-CD gene under various conditions.

• Asian-Australasian Journal of Animal Sciences
• /
• v.31 no.4
• /
• pp.467-472
• /
• 2018

Objective: Molecular cloning and bioinformatics analysis of annexin A2 (ANXA2) gene in sika deer antler tip were conducted. The role of ANXA2 gene in the growth and development of the antler were analyzed initially. Methods: The reverse transcriptase polymerase chain reaction (RT-PCR) was used to clone the cDNA sequence of the ANXA2 gene from antler tip of sika deer (Cervus Nippon hortulorum) and the bioinformatics methods were applied to analyze the amino acid sequence of Anxa2 protein. The mRNA expression levels of the ANXA2 gene in different growth stages were examined by real time reverse transcriptase polymerase chain reaction (real time RT-PCR). Results: The nucleotide sequence analysis revealed an open reading frame of 1,020 bp encoding 339 amino acids long protein of calculated molecular weight 38.6 kDa and isoelectric point 6.09. Homologous sequence alignment and phylogenetic analysis indicated that the Anxa2 mature protein of sika deer had the closest genetic distance with Cervus elaphus and Bos mutus. Real time RT-PCR results showed that the gene had differential expression levels in different growth stages, and the expression level of the ANXA2 gene was the highest at metaphase (rapid growing period). Conclusion: ANXA2 gene may promote the cell proliferation, and the finding suggested Anxa2 as an important candidate for regulating the growth and development of deer antler.

• Microbiology and Biotechnology Letters
• /
• v.14 no.2
• /
• pp.155-160
• /
• 1986

$\alpha$-Amylase gene of B. amyloliquefaciens was cloned to E. coli-yeast shuttle vector YEp-13 and expressed in E. coli. Chromosomal DNA of B. amyloliquefaciens was partially digested with Sau3Al and YEp13 plasmid was cleaved with BamH1. The hybrid plasmid, pHA28, was constructed by shotgun method and transformed to E. coli C600 and HB101. The amount of $\alpha$-amylase produced by transformants of E. coli was about 20% to 30% of that produced by B. amyloli-quefaciens. About 65% of $\alpha$-amylase produced by transformant was secreted into periplasm and the others were located in cytoplasm. $\alpha$-Amylase production was maximal when transformants were cultivated for 15hr to 20hr. As the result of agarose gel electrophoresis, pHA28 plasmid was found to be various in its size. This result suggested that pHA28 plasmid was segregated.

• Microbiology and Biotechnology Letters
• /
• v.18 no.6
• /
• pp.640-646
• /
• 1990

We have cloned the cdd gene from E. coli C600 using (cdd-) as a host. From the sequenced promoter region of E=, coli cdd gene which has been determined by Valentin-Hansen P. (1985), we synthesized the 23 mer oligonucleotides corresponding to the transcription initiation region and used as a probe for cloning of the cdd gene by Southern blotting. The isolated fragments in the blotting were introduced to the colony hybridization after transforming it into the E. coli JF611 (cdd-, pyr double mutant), and we identified the hybridized band at 27 kb long. From the original insert of 27 kb fragment in theBamHI site of pBR322, the 5.3 kb fragment containing the cdd gene was isolated by subsequent deletion and subeloning. From the derived plasmid pTK509, further deletion and subcloning were performed and clarified that the cdd gene was located in the 2.1 kb of SaZI/DraI segment in the insert of pTK605. The polypeptide encoded by the cloned DNA was appeared to be a molecular mass of 33,000.

• Microbiology and Biotechnology Letters
• /
• v.23 no.6
• /
• pp.678-686
• /
• 1995

SecY is a central component of the protein export machinery that mediate the translocation of secretory proteins across the plasma membrane of Escherichia coli. In order to study the mechanism of protein secretion in Streptomyces, we have done cloning and sequencing of the Streptomyces coelicolor secY gene by using polymerase chain reaction method. The nucleotide sequence of the gene for SecY from S. coelicolor showed over 58% identity to that of M. luteus. The deduced amino acid sequences were highly homologous to those of other known SecY polypeptides, all having the potential to form 10 transmembrane segments, and especially second, fifth, and tenth segments were particularly conserved, sharing greater than 75% identity with W. lute s SecY. We propose that the conserved membrane-spanning segments actively participate in protein export. In B. subtilis and E. coli, the secY gene is a part of the spc operon, is preceded by the gene coding for ribosomal protein L15, and is likety coupled transcriptionally and translationally to the upstream L15 gene. In the other hand, secY gene of S. coelicolor and M. luteus have its own promoter region, are coupled translationally with adk gene and pr sented in adk operon.

• 한국생물공학회:학술대회논문집
• /
• 2000.04a
• /
• pp.527-530
• /
• 2000

A kiwi fruit ,called as the Chinese gooseberry, is originated from the Yangtze River Valley of Northern China and Zhejiang Province on the cost of Eastern China. Around 1950, a large mass production began at New Zealand with an Improved breeding. Plant origin actinidin from kiwi fruit belongs to the papain family of cysteine proteinase, which in plants includes papain from papaya, bromelain from pineapple, Cl4 protease from tomato and aleurain from barley. Actinidin is involved in the ripening-related gene family. In this study, protease gene of chinese wild kiwi fruit was isolated and characterized. 1.2kb PCR-amplified fragment was obtained from the total RNA using RT-PCR. pWACT-1 was obtained by subcloning of amplified fragment into pGEM-T Easy cloning vector and analyzed nucleotide sequence by DNA sequencing and amino acid sequence. In Result, high levels of homology between wild kiwi and New Zealand cultured-kiwi was obtained.

• Microbiology and Biotechnology Letters
• /
• v.21 no.2
• /
• pp.113-118
• /
• 1993

Fro the purpose of producing glouse from cellobiose or oligo saccharide and obtaining genetic information of beta-1,4-glucosidase gene, alpha beta-1,4-glucosidase gene of Pseudomonas sp. LBC505, potent cellulase complex and xylanase producing strain, was cloned in Esherichia coli and Bacillus subtilis into pUC19 and pBD64, respectively. Recombinant plasmid pGL1 contained 1.2kb EcoRI fragment was isolated from transformants forming blue color around colony on LB agar plate containing 20 ng/ml of 5-bromo-4-chloro-3-indolyl-beta-D-glucopyranoside(X-glu) and ampicillin.

• YAKHAK HOEJI
• /
• v.37 no.5
• /
• pp.504-510
• /
• 1993

Human insulin gene is consisted of the polymorphic region with the repeating units, the regulatory sequence, the structural gene including the intervening sequence, and 3'-flanking region. The polymerase chain reaction, which amplifies the target DNA between two specific primers, has been performed for the amplification of human insulin gene and simple one-step cloning of it into Escherichia coli. Out of 1727 nuceotides compared, only 4 sites were variable: 5'-regulatory region(G2101$\rightarrow$AGG); IVS I(T2401$\rightarrow$A); Exon II(C2411 deletion); IVS II(A2740 dejection). The variations at the G2101 and T2401 were the same as those found in one American allele. The other two variations were observed only in the specific Korean allele. And, the enzyme digestion patterns among normal, insulin dependent diabetes mellitus, and non-insulin dependent diabetes mellitus were the same. On the other hand, PCR method showed the possibility of the quickaccess for the polymorphic region in terms of the restriction fragment length of polymorphism.

• BMB Reports
• /
• v.33 no.1
• /
• pp.82-88
• /
• 2000

A homologous gene to alanine racemase was cloned from a hyperthermophilic bacterium, Aquifex pyrophilus. The cloned gene encodes a protein of 341 amino acids, which has a significant homology to alanine racemase of Bacillus stearothermophilus, Lactobacillus brevis, and E. coli. When the gene was expressed in Escherichia coli, it produced a 40 kDa protein. The purified protein contains one mole pyridoxal 5-phosphate per one mole of protein, which is essential for catalytic activity of alanine racemase. The purified protein catalyzed racemization of L-alanine to D-alanine, or vice versa, indicating that the cloned gene encoded alanine racemase. It also showed significant racemization activity against L-serine and ${\alpha}-aminobutylic$ acid. The A. pyrophilus alanine racemase showed strong thermostability, and it maintained catalytic activity in the presence of organic solvents.