scholarly journals Identification, cloning and expression of the mouse N-acetylglutamate synthase gene

2002 ◽  
Vol 364 (3) ◽  
pp. 825-831 ◽  
Author(s):  
Ljubica CALDOVIC ◽  
Hiroki MORIZONO ◽  
Xiaolin YU ◽  
Mark THOMPSON ◽  
Dashuang SHI ◽  
...  
Keyword(s):  
Coli Strain ◽  
Cloning And Expression ◽  
Affinity Column ◽  
E Coli ◽  
Apparent Homogeneity ◽  
Liver Cdna Library ◽  
Targeting Signal ◽  
Acetylglutamate Synthase ◽  
Carbamylphosphate Synthetase ◽  
Allosteric Activator

In ureotelic animals, N-acetylglutamate (NAG) is an essential allosteric activator of carbamylphosphate synthetase I (CPSI), the first enzyme in the urea cycle. NAG synthase (NAGS; EC 2.3.1.1) catalyses the formation of NAG from glutamate and acetyl-CoA in liver and intestinal mitochondria. This enzyme is supposed to regulate ureagenesis by producing variable amounts of NAG, thus modulating CPSI activity. Moreover, inherited deficiencies in NAGS have been associated with hyperammonaemia, probably due to the loss of CPSI activity. Although the existence of the NAGS protein in mammals has been known for decades, the gene has remained elusive. We identified the mouse (Mus musculus) and human NAGS genes using their similarity to the respective Neurospora crassa gene. NAGS was cloned from a mouse liver cDNA library and was found to encode a 2.3kb message, highly expressed in liver and small intestine with lower expression levels in kidney, spleen and testis. The deduced amino acid sequence contains a putative mitochondrial targeting signal at the N-terminus. The cDNA sequence complements an argA (NAGS)-deficient Escherichia coli strain, reversing its arginine auxotrophy. His-tagged versions of the pre-protein and two putative mature proteins were each overexpressed in E. coli, and purified to apparent homogeneity by using a nickel-affinity column. The pre-protein and the two putative mature proteins catalysed the NAGS reaction but one of the putative mature enzymes had significantly higher activity than the pre-protein. The addition of l-arginine increased the catalytic activity of the purified recombinant NAGS enzymes by approx. 2–6-fold.

scholarly journals Non-coding sequence variants define a novel regulatory element in the first intron of the N-acetylglutamate synthase gene.

2021 ◽  
Author(s):  
Johannes Häberle ◽  
Barry Moore ◽  
Nantaporn Haskins ◽  
Véronique Rüfenacht ◽  
Dariusz Rokicki ◽  
...  
Keyword(s):  
Urea Cycle ◽  
Regulatory Element ◽  
Urea Cycle Disorder ◽  
Sequence Variants ◽  
Coding Regions ◽  
First Intron ◽  
Causes Of Disease ◽  
Acetylglutamate Synthase ◽  
Carbamylphosphate Synthetase ◽  
Allosteric Activator

N-acetylglutamate synthase deficiency (NAGSD, MIM #237310) is an autosomal recessive urea cycle disorder caused either by decreased expression of the NAGS gene or defective NAGS enzyme resulting in decreased production of N-acetylglutamate (NAG), an allosteric activator of carbamylphosphate synthetase 1 (CPS1). NAGSD is the only urea cycle disorder that can be effectively treated with a single drug, N-carbamylglutamate (NCG), a stable NAG analog, which activates CPS1 to restore ureagenesis. We describe three patients with NAGSD due to four novel sequence variants in the NAGS regulatory regions. All three patients had hyperammonemia that resolved upon treatment with NCG. Sequence variants NM_153006.2:c.-3065A>C and NM_153006.2:c-3098C>T reside in the NAGS enhancer, within known HNF1 and predicted glucocorticoid receptor binding sites, respectively. Sequence variants NM_153006.2:c.426+326G>A and NM_153006.2:c.427-218A>C reside in the first intron of NAGS and define a novel NAGS regulatory element that binds retinoic X receptor α. Reporter gene assays in HepG2 and HuH-7 cells demonstrated that all four substitutions could result in reduced expression of NAGS. These findings show that analyzing non-coding regions of NAGS and other urea cycle genes can reveal molecular causes of disease and identify novel regulators of ureagenesis.

Cloning and expression of the beta-D-phosphogalactoside galactohydrolase gene of Lactobacillus casei in Escherichia coli K-12

1982 ◽  
Vol 152 (3) ◽  
pp. 1138-1146
Author(s):  
L J Lee ◽  
J B Hansen ◽  
E K Jagusztyn-Krynicka ◽  
B M Chassy
Keyword(s):  
Escherichia Coli ◽  
Lactobacillus Casei ◽  
Specific Activity ◽  
Protein Product ◽  
Coli Strain ◽  
Cloning And Expression ◽  
E Coli ◽  
Lactose Metabolism ◽  
Gene Coding ◽  
K 12

Lactose metabolism in Lactobacillus casei 64H is associated with the presence of plasmid pLZ64. This plasmid determines both phosphoenolpyruvate-dependent phosphotransferase uptake of lactose and beta-D-phosphogalactoside galactohydrolase. A shotgun clone bank of chimeric plasmids containing restriction enzyme digest fragments of pLZ64 DNA was constructed in Escherichia coli K-12. One clone contained the gene coding for beta-D-phosphogalactoside galactohydrolase on a 7.9-kilobase PstI fragment cloned into the vector pBR322 in E. coli strain chi 1849. The beta-D-phosphogalactoside galactohydrolase enzyme isolated from E. coli showed no difference from that isolated from L. casei, and specific activity of beta-D-phosphogalactoside galactohydrolase was stimulated 1.8-fold in E. coli by growth in media containing beta-galactosides. A restriction map of the recombinant plasmid was compiled, and with that information, a series of subclones was constructed. From an analysis of the proteins produced by minicells prepared from transformant E. coli cells containing each of the recombinant subclone plasmids, it was found that the gene for the 56-kilodalton beta-D-phosphogalactoside galactohydrolase was transcribed from an L. casei-derived promoter. The gene for a second protein product (43 kilodaltons) was transcribed in the opposite direction, presumably under the control of a promoter in pBR322. The relationship of this second product to the lactose metabolism genes of L. casei is at present unknown.

Cloning and expression of S-Adenosyl Methionine (SAMe) Synthetase gene in recombinant E. coli strain for large scale production of SAMe

2010 ◽  
Vol 13 (4) ◽  
Author(s):  
Swaminathan Detchanamurthy ◽  
Kirubanandan Shanmugam ◽  
Salai Madhumathi Arasi Parkunan ◽  
Shilpa Puttananjaiah ◽  
Balaji Somasundaram ◽  
...  
Keyword(s):  
Large Scale ◽  
Coli Strain ◽  
Cloning And Expression ◽  
Scale Production ◽  
E Coli ◽  
Large Scale Production ◽  
Adenosyl Methionine

scholarly journals Cloning and gene expression equine leukocyte α-interferon in cells of Escherichia Coli

2013 ◽  
Vol 12 (1) ◽  
pp. 82
Author(s):  
A. A. Muttar
Keyword(s):  
Interferon Alpha ◽  
Coli Strain ◽  
Innate Immune ◽  
Cloning And Expression ◽  
Innate Immune Responses ◽  
E Coli ◽  
Strain Bl21 ◽  
The Matrix ◽  
Interferon Gene

Interferon plays role in innate immune responses through upregulation of costimulatory molecules and induction of proinflammatory cytokines. interferons including interferon alpha (IFNA). The present study characterized IFNA cDNA and predicted protein. The interferon’s play a great role in protection from infections, which have been called by microorganisms, and also have powerful antiproliferation and immunomodulation activity. The purposes of study: cloning and expression of horse leukocyte interferon and purification the product protein. The results and discussion : In the result we isolated (DNA) from equine leukocyte in blood, which was used in the quality of the matrix for amplification of α-interferon gene with PCR HELP, and isolation gene α-interferon and transformation in vector puc18 and expression vector PET24b (+) and recombinant plasmid was transformed into E. coli strain BL21( codon plus 440) induction with IPTG. The results showed the protein having the same molecular weight as horse interferon alpha about 5.81 kDa

scholarly journals Gene delivery corrects N-acetylglutamate synthase deficiency and enables insights in the physiological impact of L-arginine activation of N-acetylglutamate synthase

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
P. Sonaimuthu ◽  
E. Senkevitch ◽  
N. Haskins ◽  
P. Uapinyoying ◽  
M. McNutt ◽  
...  
Keyword(s):  
Ammonia Concentration ◽  
Ammonia Toxicity ◽  
Wild Type ◽  
Adeno Associated Virus ◽  
The Central Nervous System ◽  
Acetylglutamate Synthase ◽  
Physiological Impact ◽  
Carbamylphosphate Synthetase ◽  
Allosteric Activator

AbstractThe urea cycle protects the central nervous system from ammonia toxicity by converting ammonia to urea. N-acetylglutamate synthase (NAGS) catalyzes formation of N-acetylglutamate, an essential allosteric activator of carbamylphosphate synthetase 1. Enzymatic activity of mammalian NAGS doubles in the presence of L-arginine, but the physiological significance of NAGS activation by L-arginine has been unknown. The NAGS knockout (Nags−/−) mouse is an animal model of inducible hyperammonemia, which develops hyperammonemia without N-carbamylglutamate and L-citrulline supplementation (NCG + Cit). We used adeno associated virus (AAV) based gene transfer to correct NAGS deficiency in the Nags−/− mice, established the dose of the vector needed to rescue Nags−/− mice from hyperammonemia and measured expression levels of Nags mRNA and NAGS protein in the livers of rescued animals. This methodology was used to investigate the effect of L-arginine on ureagenesis in vivo by treating Nags−/− mice with AAV vectors encoding either wild-type or E354A mutant mouse NAGS (mNAGS), which is not activated by L-arginine. The Nags−/− mice expressing E354A mNAGS were viable but had elevated plasma ammonia concentration despite similar levels of the E354A and wild-type mNAGS proteins. The corresponding mutation in human NAGS (NP_694551.1:p.E360D) that abolishes binding and activation by L-arginine was identified in a patient with NAGS deficiency. Our results show that NAGS deficiency can be rescued by gene therapy, and suggest that L-arginine binding to the NAGS enzyme is essential for normal ureagenesis.

Transport of escherichia coli through soil to groundwater traced by randomly amplified polymorphic DNA (RAPD)

1997 ◽  
Vol 35 (11-12) ◽  
pp. 351-357 ◽  
Author(s):  
R. Rothmaier ◽  
A. Weidenmann ◽  
K. Botzenhart
Keyword(s):  
Negative Impact ◽  
Random Amplified Polymorphic Dna ◽  
Coli Strain ◽  
Soil Samples ◽  
Test Field ◽  
Liquid Manure ◽  
E Coli ◽  
Rapd Pattern ◽  
Geological Situation ◽  
Different Strains

Isolates (50) of E. coli obtained from liquid manure (20 bovine, 20 porcine) were genotyped using random amplified polymorphic DNA (RAPD). Typing revealed 9 and 14 different strains in bovine and porcine liquid manure respectively with no strains in common. One porcine strain, showing a simple RAPD pattern, was subcultured and spread on a test field (1.5l/m2 at 1010 cfu/l) in a drinking water protection zone with loamy to sandy sediments in the Donauried area, Baden-Wurttemberg. Soil samples and groundwaters were collected at monthly intervals October 1994 – June 1995 during which 114 E. coli isolates were recovered. The first occurrence and maximum concentration of E. coli in soil samples taken from more than 20cm depth was in January 1995, declining rapidly with depth and time. All isolates from soil and only one from groundwater showed the RAPD pattern of the spread E. coli strain. The results could not demonstrate a severe negative impact of the spreading of liquid manure on the bacteriological quality of the groundwater in the given geological situation. The distinct strain patterns found in different kinds of liquid manure suggest that genotyping of E. coli by RAPD may be an adequate tool for tracing sources of faecal contamination.

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