• Title/Summary/Keyword: HPr

Search Result 47, Processing Time 0.023 seconds

Characterization of a Bifunctional HPr Kinase/Phosphorylase from Leuconostoc mesenteroides SY1

  • Park, Jae-Yong;Lee, Kang-Wook;Lee, Ae-Ran;Jeong, Woo-Ju;Chun, Ji-Yeon;Lee, Jong-Hoon;Kim, Jeong-Hwan
    • Journal of Microbiology and Biotechnology
    • /
    • v.18 no.4
    • /
    • pp.746-753
    • /
    • 2008
  • The hprK gene encoding bifunctional HPrK/P (kinase/phosphorylase) was cloned from L. mesenteroides SY1, a strain isolated from kimchi. hprK was transcribed as a monocistronic gene. His-tagged HPrH16A and HPrK/P were produced in E. coli BL21 (DE3) using pET26b(+) and purified. HPrK/P phosphorylation assay with purified proteins showed that the kinase activity of HPrK/P increased at slightly acidic pHs. Divalent cations such as $Mg^{2+}$ and $Mn^{2+}$ and glycolytic intermediates such as fructose-1, 6-bisphosphate (FBP) and phosphoenolpyruvate (PEP) increased the kinase activity of HPrK/P, but inorganic phosphate strongly inhibited it. Kinetic studies for the kinase activity of HPrK/P showed that the apparent $K_m$ values were 0.18 and $14.57{\mu}M$ for ATP and HPr, respectively. The $K_m$ value for the phosphorylase activity of HPrK/P was $14.16{\mu}M$ for P-Ser-HPr (HPr phosphorylated at the serine residue).

Brain Vesicle Structure and Formation of the Hydrostatic Pressure Receptors in Larvae of the Ascidian (Halocynthia roretzi) (우렁쉥이(Halocynthia roretzi) 유생의 뇌포 구조와 수압수용쳬의 형성)

  • Kim Jung-Eun;Seo Hyeong-Joo;Kim Gil-Jung
    • Korean Journal of Fisheries and Aquatic Sciences
    • /
    • v.39 no.2
    • /
    • pp.94-99
    • /
    • 2006
  • The tadpole larvae of most ascidians have two sensory pigment cells in their brain vesicle. The anterior otolith pigment cell is sensitive to gravity, whereas the posterior ocellus pigment cell responds to light. Besides these two sensory cells, the larvae also possess another type of sensory receptor cell: hydrostatic pressure receptor (Hpr) cells. The Hpr cells have been presumed to sense hydrostatic water pressure, although no functional analysis has been performed. In larvae of the ascidian Halocynthia reretzi, the development of the Hpr cells and their structure in the brain vesicle are poorly understood. To investigate the morphology and formation of the Hpr cells, we established a monoclonal antibody, Hpr-1, that specifically recognizes Hpr cells. The Hpr-1 antigens became detectable in the brain vesicle at the late tailbud stage. Each Hpr cell projected a small globular body, connected by a short stalk, into the lumen of the brain vesicle. The brain vesicle showed remarkable left-right asymmetry. Pigment cells were located on the right side in the lumen of the brain vesicle, whereas Hpr cells were present in the left side. After metamorphosis, the Hpr cells were observed near the rudimental siphons of the juvenile.

Regulation of Glycogen Concentration by the Histidine-Containing Phosphocarrier Protein HPr in Escherichia coli

  • Koo, Byung-Mo;Seok, Yeong-Jae
    • Journal of Microbiology
    • /
    • v.39 no.1
    • /
    • pp.24-30
    • /
    • 2001
  • In addition to effecting the catalysis of sugar uptake, the bacterial phosphoenolpyruvate::sugar phosphotransferase system regulates a variety of physiological processes. In a previous paper [Seok et al.,(1997) J. Biol. Chem. 272, 26511-26521], we reported the interaction with and allosteric regulation of Esiherichia coli glycogen phosphorylase activity by the histidine-containing phosphocarrier protein HPr in vitro. Here, we show that the specific interaction between HPr and glycogen phosphorylase occurs in vivo. To address the physiological role of the HPr-glycogen phosphorylase complex, intracellular glycogen levels were measured in E. coli strains transformed with various plasmids. While glycogen accumulated during the transition between exponential and stationary growth phases in wildtype cells, it did not accumulate in cells overproducing HPr or its inactive mutant regardless of the growth stage. From these results, we conclude that HPr mediates crosstalk between sugar uptake through the phosphoenolpyruvate:sugar phosphotransferase system and glycogen breakdown. The evolutionary significance of the HPr-glycogen phosphorylase complex is suggested.

  • PDF

Role of FGF and MEK Signaling in Formation of the Hydrostatic Pressure Receptor Cells during Ascidian Embryogenesis (멍게의 수압수용체세포 형성에서 FGF와 MEK 신호의 역할)

  • Seo, Hyeong-Joo;Kim, Gil-Jung
    • Development and Reproduction
    • /
    • v.13 no.4
    • /
    • pp.291-296
    • /
    • 2009
  • In most larvae of ascidian, two sensory pigment cells, otolith and ocellus, lie in their brain vesicle. They also have a third type of sensory cells: hydrostatic pressure receptor (Hpr) cells. The Hpr cells were presumed to be hydrostatic pressure-detection cells, but their precise functions is still disputed. In this study, we investigated whether an FGF signaling is involved in formation of Hpr cells. When fertilized eggs were injected with Hr-FGF9/16/20 antisense MO, the resulting larvae showed severe abnormalities with no expression of the Hpr cell-specific Hpr-1 antigen. Similar results were obtained using an FGF receptor inhibitor, SU5402, and an MEK inhibitor, U0126. Embryos treated with SU5402 or U0126 during the 32-cell and hatching stages did not express the Hpr-1 antigen. To elucidate the temporal requirement for the FGF signaling in formation of Hpr cells, embryos were treated with SU5402 for 2 h, or U0126 for 20 min during various embryonic stages. Larvae treated with SU5402 from the 16-cell stage to the 64-cell stage did not express the Hpr-1 antigen, whereas those treated at the early gastrula stage expressed the Hpr-1 antigen. When U0126 treatment was carried out at various stages between the 8-cell and late gastrula stages, larvae scarcely formed the Hpr cells. They showed expression of the Hpr-1 antigen when embryos were placed in U0126 just before the neural plate stage. These results suggest that FGF9/16/20 signaling is involved in formation of Hpr cells from the primary neural induction stage to the late gastrula stage.

  • PDF

Skin Wrinkle Improvement Effect of Paeoniae radix and processed Paeoniae radix Through inhibition of Advanced glycation end products (AGEs) (작약 및 포제작약의 최종당화산물 억제를 통한 피부 주름 개선 효과)

  • Kim, SuJi;Lee, AhReum;Kim, SooHyun;Kim, KyeongJo;Kwon, OJun;Choi, JoonYoung;Koo, JinSuk;Roh, Seong-Soo
    • The Korea Journal of Herbology
    • /
    • v.32 no.4
    • /
    • pp.53-60
    • /
    • 2017
  • Objectives : Collagen decrease of Skin appears through various path ways. One of causes may be the Advanced glycation endproducts (AGEs) that combine formation of glucose and protein. The aim of this study was to explore the prevent wrinkle formation of Paeoniae radix (PR) and heated Paeoniae radix (HPR) via AGEs path way. Methods : AGEs formation inhibitory activities of PR and HPR measured using bovine serum albumin, glucose, and fructose. To evaluate the protective effects of PR and HPR in diabetic rats induced with streptozotocin (STZ) and methyl glyoxal (MGO), SD rat were distributed into four groups. Normal rats (Nor), AGEs-induced rats (Con), AGEs-induced rats treated with 100 mg/kg PR(PR), AGEs-induced rats treated with 100 mg/kg HPR (HPR). To induce AGEs, streptozotocin (50 mg/kg) was administered intraperitoneally and after 3 days administrated 100mM methyl glyoxal for 3 weeks. Results : The oral administration of HPR inhibited AGEs in skin tissues compared with PR. The increased reactive oxygen species (ROS) levels in the serum were diminished by HPR treatment. The analyses of kidney and skin tissues proteins indicated that HPR treatment effectively reduced AGEs related protein levels as compared to that by PR treatment. Also, HPR decreased anti-oxidant related protein levels in skin tissues such as catalase, glutathione peroxidase. Moreover, it inhibited the reduction of COL1A2 by decreasing MMP-1. Conclusion : Based on these results, it was suggested that PR and HPR could have Improving effects on wrinkle formation. These evidences provide useful information for the development wrinkle formation treated agent.

Characterization of ptsHI Operon from Leuconostoc mesenteroides SY1, a Strain Isolated from Kimchi

  • Park Jae-Yong;Jeong Seon-Ju;Chun Ji-Yeon;Lee Jong-Hoon;Chung Dae-Kyun;Kim Jeong-Hwan
    • Journal of Microbiology and Biotechnology
    • /
    • v.16 no.6
    • /
    • pp.988-992
    • /
    • 2006
  • The ptsHI operon from Leuconostoc mesenteroides ssp. mesenteroides SY1 (L. mesenteroides SY1), a strain isolated from kimchi, was cloned and characterized. The ptsH open reading frame (ORF) was 273 bp in size, which can encode a protein of 90 amino acid residues with a molecular weight of 9,212 Da. The pfsI ORF was 1,719 bp in size, which was capable of encoding a protein of 572 amino acids with a molecular mass of 62,549 Da. ptsH and pfsI genes were transcribed as a single transcript of 2.0 kb in size regardless of carbon sources, supporting the operon structure. Although the deduced amino acid sequences of the HPr and EI were highly homologous with those of other Gram-positive bacteria, an additional amino acid (glutamine at the $3^{rd}$ amino acid) was present in HPr from L. mesenteroides SY1. Phosphorylation sites of HPr included the histidine residue ($16^{th}$) and serine residue ($47^{th}$). Mutant HPrs, in which each phosphorylation site was mutated into alanine, were obtained, and phosphorylation with HPr and mutated HPrs showed that HPr was phosphorylated at the serine residue ($47^{th}$) by HPr kinaseiphosphorylase (HPr K/P).

Effects of the Repression of sphpr1 Expression on Growth and mRNA Export in Fission Yeast (분열효모에서 sphpr1 유전자의 결실이 생장 및 mRNA Export에 미치는 영향)

  • Lee, Hyun-Joo;Yoon, Jin-Ho
    • Korean Journal of Microbiology
    • /
    • v.48 no.2
    • /
    • pp.171-174
    • /
    • 2012
  • THOC1/Hpr1 is one subunit of THO complex that is an evolutionally conserved assembly involved in the mRNP packaging and mRNA export during transcription elongation. In fission yeast Schizosaccharomyces pombe, an ortholog (spHpr1) of THOC1/Hpr1 was identified based on sequence alignment. A deletion mutant in a diploid strain was constructed by replacing one of spHpr1-coding region with a $kan^r$ gene using one-step gene disruption method. Tetrad analysis showed that the sphpr1 is essential for growth. Over-expression of sphpr1 from strong nmt1 promoter caused no defects of growth and mRNA export. However, repression of the sphpr1 expression resulted in growth inhibition accompanied by accumulation of poly$(A)^+$ RNA in the nucleus. These results suggest that spHpr1 is involved in mRNA export from the nucleus to cytoplasm.

The Physico-Chemical Characteristics of Modified Starch Made by Chemical Treatment (화학적 처리방법에 의한 변성전분의 이화학적 특성)

  • Song, Eun-Seung;Woo, Na-Ri-Yah
    • Journal of the Korean Society of Food Culture
    • /
    • v.22 no.1
    • /
    • pp.91-96
    • /
    • 2007
  • Developing carbohydrate fat replacer as materials for low-calorie and low-fat food made of Korean potato, it is expected that the new demand of fat replacer will be created. Potato starch was modified by chemical modification. Observing modified starch(treated in different method) by SEM, EZ(treated by enzyme) showed shape of deformed round oval, AC(treated by acetylation,), HPR(treated by hydropropylation) showed shape similar to that of NL(N-Lite), the commercial fat replacer. In the modified starch such as AC, peak in B and C type similar to those of general starch was found, but EZ showed non-crystalline shape. Compared to other modified starch, HPR, the chemically produced denatured starch showed very peculiar peak and structure in V-form. While the order of contents of amylopectin was in the order HPR > EZ > AC showed extremely high contents. Measuring the degree of gelatinization per the modified method, the degree of gelatinization of HPR as much higher than others. The water binding activity of modified starch was 240% in HPR. Measuring viscosity by producing general starch and modified starch as gel of 10% concentration, the CPS showed very high viscosity of 30.30 ${\times}$ 10$^3$ cp. Showing viscosity of 38.60, 31.60 10$^3$ ${\times}$ cp, the modified starch was in the order of HPR. While the calorie of starch of GPS was measured to be 3.0 Kcal/g, very low calorie those of chemically modified starch, HPR showed 2.5 Kcal/g respectively, suggesting that calorie is decreased by modified treatment. The appropriateness of processing food was experimented by substituting the existing oil and fat containing food with saturated gel of starch and modified starch in constant rate through utilization of modified starch. Therefore, research and development for materials and related products which maintain the existing quality and reduce fat contents will be constantly performed in the future.

Growth, Blood Metabolites, and Health of Holstein Calves Fed Milk Replacer Containing Different Amounts of Energy and Protein

  • Lee, H.J.;Khan, M.A.;Lee, W.S.;Kim, H.S.;Ki, K.S.;Jang, S.J.;Hur, T.Y.;Khan, M.S.;Choi, Y.J.
    • Asian-Australasian Journal of Animal Sciences
    • /
    • v.21 no.2
    • /
    • pp.198-203
    • /
    • 2008
  • This study was conducted to compare the effects of feeding high protein and low energy milk replacer (HPR; CP 25%, ME 3.6 Mcal/kg DM) with low protein and high energy milk replacer (HPR; CP 21%, ME 4.2 Mcal/kg DM) on feed consumption, body weight (BW) gain, health and selected blood metabolites in Holstein calves during the pre-weaning period. At each feeding, each milk replacer (MR) was prepared by mixing 0.125 kg of dry MR in 1L of warm ($60^{\circ}C$) water. The calves were fed either HPR (n = 10) or HER (n = 10) using mobile plastic bottles fitted with soft rubber nipples. All calves received 1.8L diluted MR at each feeding 3 times daily during the first 4 weeks of age; feeding frequency was reduced to 2 times daily for the next 2 weeks of age and then to once daily during the last week of the experiment. Jugular blood was sampled in calves at day 7, 14, 21, 35 and 49 of age to enumerate selected metabolites. Daily MR, starter and hay intake during the pre-weaning period were similar in calves fed HPR and HER. Consumption of starter, MGH and total DM steadily increased with the age of calves. Final BW, daily BW gain and feed efficiency of calves were not affected by treatments. Serum glucose, cholesterol, creatinine were decreased (p<0.05) and blood urea N was increased (p<0.05) in calves fed HER or HPR as they grew older. Serum glucose, total protein and albumin concentrations in calves were not affected by treatments. Serum GPT and GOT concentrations were higher (p<0.05) in calves on HPR than on HER. Scouring score, days scoured, respiratory score, rectal temperature and general appearance were similar in calves fed HPR and HER. Poor general appearance (dullness and droopy ears) of calves fed either HPR or HER reflected nutritional insufficiency and stress. In conclusion, energy and protein concentrations in MR did not affect feed intake and BW gain in Holstein calves during the pre-weaning period. Poor general appearance and lower BW gain of calves compared to those reported in the literature for milk fed calves prompt a demand for further research to improve the daily nutrient supply to MR-fed calves.

Interaction for Phosphotransfer between N-Terminal Domain of Enzyme I and HPr of E. coli Phosphoenolpyruvate:Sugar Phosphotransferase System.

  • Seok, Yeong-Jae
    • Proceedings of the Korean Biophysical Society Conference
    • /
    • 1998.06a
    • /
    • pp.12-12
    • /
    • 1998
  • The interaction between the N-terminal domain of enzyme I (EIN) and the histidine-containing phosphocarrier protein HPr of the Escherichia coli phosphoenolpyruvate:sugar phosphotransferase system has been investigated by Isothermal Titration Calorimetry and heteronuclear magnetic resonance spectroscopy.(omitted)

  • PDF