• Journal of Microbiology and Biotechnology
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• 제14권3호
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• pp.635-638
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• 2004

An ATP-binding-cassette (ABC) transporter gene in the cephabacin biosynthetic gene cluster of Lysobacter lactamgenus was characterized. The amplified orf10 (cpbJ) gene was subcloned into pET-28a(+) vector and expressed in E. coli BL21(DE3) strain by 0.5 mM IPTG at $30^{\circ}C$. The membrane fraction of recombinant E. coli cells was separated by ultracentrifugation, and solubilized using 2.5% octyl-$\beta$-D-glucoside. Using the solubilized membrane fraction, the artificial proteoliposomes were reconstituted and analyzed for the biological activity of CpbJ protein. Upon measuring ATPase activity, the proteoliposome made from recombinant E. coli membrane proteins showed slightly higher activity than that from host E. coli membrane proteins. In the measurement of membrane transport activity, the reconstituted proteoliposome of recombinant E. coli membrane proteins exhibited higher activity when both substrates of cephalosporin C and L-Ala-L-Ser were applied, compared to the case of cephalosporin C or L-Ala-L-Ser only. It implies that the CpbJ protein is an ABC transporter secreting cephabacin antibiotics synthesized in cytoplasm.

• BMB Reports
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• 제31권1호
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• pp.70-76
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• 1998

The final step in ethylene biosynthesis is catalyzed by the enzyme 1-aminocyclopropane-1-carboxylate (ACC) oxidase. ACC oxidase was extracted from mung bean hypocotyls and its biochemical characteristics were determined. In vitro ACC oxidase activity required ascorbate and $Fe^{2+}$, and was enhanced by sodium bicarbonate. Maximum specific activity (approximately 20 nl ethylene $h^{-1}$ mg $protein^{-1}$) was obtained in an assay medium containing 100 mM MOPS (pH 7.5), $25\;{\mu}M$ $FeSO_4$, 6 mM sodium ascorbate, 1 mM ACC, 5 mM sodium bicarbonate and 10% glycerol. The apparent $K_m$ for ACC was $80{\pm}3\;{\mu}M$. Pretreating mung bean hypocotyls with ethylene increased in vitro ACC oxidase activity twofold. ACC oxidase activity was strongly inhibited by metal ions such as $Co^{2+}$, $Cu^{2+}$, $Zn^{2+}$, and $Mn^{2+}$, and by salicylic acid. Inactivation of ACC oxidase by salicylic acid could be overcome by increasing the $Fe^{2+}$ concentration of the assay medium. The possible mode of inhibition of ACC oxidase activity by salicylic acid is discussed.

• Biotechnology and Bioprocess Engineering:BBE
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• 제11권1호
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• pp.32-37
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• 2006

In this study, we have purified and characterized the membrane bound nitrate reductase obtained from the denitrifying bacteria, Ochrobactrum anthropi SY509, which was isolated from soil samples. O. anthropi SY509 can grow in minimal medium using nitrate as a nitrogen source. We achieved an overall purification rate of 15-fold from the protein extracted from the membrane fraction, with a recovery of approximately 12% of activity. The enzyme exhibited its highest level of activity at pH 5.5, and the activity was increased up to $70^{\circ}C$. Periplasmic and cytochromic proteins, including nitrite and nitrous oxide reductase, were excluded during centrifugation and were verified using enzyme essay. Reduced methyl viologen was determined to be the most efficient electron donor among a variety of anionic and cationic dyestuffs, which could be also used as an electron donor with dimethyl dithionite. The effects of purification and storage conditions on the stability of enzyme were also investigated. The activity of the membranebound nitrate reductase was stably maintained for over 2 weeks in solution. To maintain the stability of enzyme, the cell was disrupted using sonication at low temperatures, and enzyme was extracted by hot water without any surfactant. The purified enzyme was stored in solution with no salt to prevent any significant losses in activity levels.

• 한국육종학회지
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• 제40권4호
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• pp.422-429
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• 2008

본 실험에서 Lilium longiflorum과 11품종에 대한 biochemical, enzymology 등의 분석방법을 적용하여, 화색생합성조절유전자 chalcone synthase(CHS), flavanone 3-hydroxylase(FHT)의 활성을 분석한 결과는 다음과 같다. 1. Flavonoid의 기본골격형성을 위한 첫 효소인 CHS가 malonyl-CoA와 p-coumaroyl-CoA 기질을 촉매하여 naringenin(NAR) 산물을 생성하였고, caffeoyl-CoA와 p-coumaroyl-CoA 기질에는 eridictiol(ERI)를 생성하지 않아, 백합의 CHS는 기질특이성을 나타냈다. 2. L. longiflorum에서 FHT 효소는 NAR를 기질로써 사용하여, dihydrokaempferol(DHK) 산물을 생성하였고, 그 외 11백합품종에서도 FHT 효소의 뚜렷한 활성이 확인되었다.

• Asian-Australasian Journal of Animal Sciences
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• 제15권8호
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• pp.1215-1221
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• 2002

Normal haematological and biochemical indices along with thyroid hormone status were studied in healthy Kathiawari horses of different age groups (yearling, young stock, adults and old stock) belonging to either sex. Effect of both age and sex was observed on thyroid hormone levels, haematological and biochemical indices. In females, hemoglobin levels was significantly lower in yearlings than adult animals while total leukocyte counts were higher in yearlings than equids of other age groups. Sex had effect only on total erythrocyte counts, mean corpuscular hemoglobin concentration and mean corpuscular hemoglobin in horses of 1-3 years age group (young stock) and on packed cell volume in adult female and male equids. Among biochemical indices, activities of enzymes were observed to be influenced both by age and sex. Creatine kinase, gamma glutamyl transferase, glutamate pyruvate transaminase, glutamic oxaloacetate transaminase and lactate dehydrogenase activities were significantly higher in young and adult equids than animals of other age groups in Kathiawari horses while activity of alkaline phosphatase was significantly higher in yearlings than equids belonging to other age groups in both male and females. However, activity of sorbitol dehydrogenase was unaltered due to both sex and age factor. Albumin, bilirubin direct, bilirubin total, cholesterol, creatinine, protein, triglyceride and uric acid were statistically different in various age and sex groups of horses. Calcium, magnesium and chloride contents were almost same in various age groups of male horses. Significantly higher levels of $T_3$ and $T_4$ were observed in both male and female yearlings as compared to equids of other age groups in both the sexes.

• Biotechnology and Bioprocess Engineering:BBE
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• 제11권6호
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• pp.530-537
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• 2006

Recently isolated, Pseudomonas putida SN1 grows on styrene as its sole carbon and energy source through successive oxidation of styrene by styrene monooxygenase (SMO), styrene oxide isomerase (SOI), and phenylacetaldehyde dehydrogenase. For the production of (S)-styrene oxide, two knockout mutants of SN1 were constructed, one lacking SOI and another lacking both SMO and SOI. These mutants were developed into whole-cell biocatalysts by transformation with a multicopy plasmid vector containing SMO genes (styAB) of the SN1. Neither of these self-cloned recombinants could grow on styrene, but both converted styrene into an enantiopure (S)-styrene oxide (e.e. > 99%). Whole-cell SMO activity was higher in the recombinant constructed from the SOI-deleted mutant (130 U/g cdw) than in the other one (35 U/g cdw). However, the SMO activity of the former was about the same as that of the SOI-deleted SN1 possessing a single copy of the styAB gene that was used as host. This indicates that the copy number of styAB genes is not rate-limiting on SMO catalysis by whole-cell SN1.

• Asian-Australasian Journal of Animal Sciences
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• 제13권9호
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• pp.1210-1218
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• 2000

Four experiments were conducted to evaluate the effect of temperature and humidity on biochemical indices of Arbor Acres broilers at different weeks of age. The alkaline phosphatase (AKP), acid phosphatase (ACP), lactic dehydrogenase (LD), creatine kinase (CK), plasma glucose (Glu), calcium (Ca), potassium (K), chloride (Cl), urea nitrogen (UN), uric acid (UA), plasma thyroxin (T4), triiodothyronine (T3) and insulin levels were determined in all the four experiments. In experiment 1, the plasma Glu, LD and CK levels were increased by heat exposure ($35{^{\circ}C}$ and 35, 60, or 85% RH, 2 h) and this effect was aggravated by longer exposure (24 h). No significant changes (p>0.05) were found in Ca concentration, activity of AKP and ACP. In experiment 2, temperature (10, 20, 30, $33{^{\circ}C}$) had significant effect on the levels of K, Cl, UN, UA levels and the activity of LD (p<0.01), but had no significant influence on the activity of CK (p>0.05). The UN, UK and LD levels were elevated by low temperature $(10{^{\circ}C})$ (p<0.01), Cl content was increased by high temperature ($(33{^{\circ}C})$ (p<0.01), and K level was decreased by high ($(33{^{\circ}C})$ or low $(10{^{\circ}C})$ temperature and increased by medium temperature $(30{^{\circ}C})$ (p<0.01). The humidity (35, 85% RH) only had significant effect on Cl concentration which was decreased by high humidity (p<0.01). In experiment 3, the result showed that only the LD and CK activity were significantly increased (p<0.01) by high temperature (7, 24, 28, $32{^{\circ}C}$) or high humidity (35, 85% RH). Temperature and humidity had no significant effect on K, Cl, UA, UN and Glu levels (p>0.05). In experiment 4 (24, 27, 30, $33{^{\circ}C}$; 30, 45, 60, 75, 90% RH), plasma T3 level was declined by high temperature $(33{^{\circ}C})$, and this phenomena disappeared in birds under high temperature and high humidity environment. T4 concentration in plasma was not affected by temperature (p>0.05), but was increased by high or low humidity (p<0.01). Neither temperature nor humidity had significant effect on plasma insulin concentration (p>0.05). The results of the four experiments suggested that broilers at different growth periods might have different thermal requirements and would response differently to heat exposure. The plasma biochemical indices themselves had big variation; the reaction of the indices to thermal exposure treatment differed with the age of broilers. The big variation of biochemical indices themselves might cover the response of indices to temperature and humidity treatments.

• Asian-Australasian Journal of Animal Sciences
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• 제23권9호
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• pp.1221-1228
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• 2010

This study aimed to examine the effect of overfeeding on biochemical parameters and lipoprotein-lipase (LPL) mRNA expression in different tissues associated with hepatic lipogenesis in Sichuan white and Landes geese. Fifty healthy male Sichuan white geese and fifty male Landes geese (Cygnus atratus) were hatched on the same day under the same feeding conditions and were selected as experimental animals. After overfeeding for 14 days (from 14 weeks to 16 weeks) and then slaughtering, the biochemical changes of hepatic lipogenesis were evaluated. Results showed that i) in Landes geese, the plasma concentration of glucose was higher (p<0.001), while plasma concentrations of insulin and VLDL were both lower (p<0.01); ii) the LPL mRNA level in pectoralis muscle and leg muscle of the overfed groups in both breeds was higher (p<0.05) than in the control groups; iii) in Sichuan white geese, the proportion of fatty liver weight was positively correlated with plasma triacylglycerols (TG)(p<0.05) and VLDL concentrations (p<0.05), while these correlations were not significant in Landes geese; and iv) the activity of LPL had significant positive correlation with the proportions of lipids in subcutaneous adipose tissue and abdominal adipose tissue in Sichuan white geese, while in Landes geese the correlation was negative (p<0.05) with proportions of lipids in the liver, LPL activity had a significant positive correlation with the proportions of lipids in subcutaneous adipose tissue. These results suggest that the Landes geese have a better ability to use the massive amount of ingested food and to store lipids preferentially in the liver, but the Sichuan white geese have a relatively lower ability to use energetic nutrients and lipid storage is more efficient in the adipose tissues.

• Journal of Ginseng Research
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• 제16권3호
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• pp.228-234
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• 1992

There has been general tendency to explain the traditional ginseng efficacy through the pharmacological and biochemical activities of ginsenosides. However, when we analyze the pharmacological and biological data on ginseng reported yet, we can easily arrive at the conclsion that most of the data on pharmacological and biological activities must have been obtained using impure ginsenoside samples, which should contain some non-saponin constituents as impurities. Based on the above back-ground, the non-saponin constituents of ginseng were studied in our laboratory. Phenolic substances including Maltol, Vanillic Acid, Salicylic Acid, Ferrulic Acid and Caffeic acid and impure ginsenoside samples were found to show strong antioxidant and anti-fatigue activities, while pure ginsenosides were devoid of the activities. Maltol, one of antioxidant components In Korean red ginseng drew a special interest due to its very low pro-oxidant activity. The antioxidant activity of ginseng may be considered as scientific basis for the antiageing activity which was described in traditional medicinal material book as "long-term medication of ginseng will improve bio-efficiency and extend life-span" The lignin components, another non-saponin consitutents, isolated from ginseng extract In our laboratory may eplain the hepato-protective activity of ginseng which has been repeatedly rtaimed as one of the efficacies of ginsenosides. The P-carboline alkaloids isolated in our laboratory as one of the non-saponin constituents of ginseng may play some pharmacological activities which should also be investigated. Present paper will include chemistry and biochemical aspects of the non-saponin constituents of ginseng with special interests for the explanation of traditional ginseng efficacy on modern scientific basis.fic basis.

• Journal of Microbiology and Biotechnology
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• 제31권3호
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• pp.464-474
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• 2021

Bacterial cytochrome P450 (CYP) enzymes are responsible for the hydroxylation of diverse endogenous substances with a heme molecule used as a cofactor. This study characterized two CYP154C3 proteins from Streptomyces sp. W2061 (CYP154C3-1) and Streptomyces sp. KCCM40643 (CYP154C3-2). The enzymatic activity assays of both CYPs conducted using heterologous redox partners' putidaredoxin and putidaredoxin reductase showed substrate flexibility with different steroids and exhibited interesting product formation patterns. The enzymatic characterization revealed good activity over a pH range of 7.0 to 7.8 and the optimal temperature range for activity was 30 to 37℃. The major product was the C16-hydroxylated product and the kinetic profiles and patterns of the generated hydroxylated products differed between the two enzymes. Both enzymes showed a higher affinity toward progesterone, with CYP154C3-1 demonstrating slightly higher activity than CYP154C3-2 for most of the substrates. Oxidizing agents (diacetoxyiodo) benzene (PIDA) and hydrogen peroxide (H2O2) were also utilized to actively support the redox reactions, with optimum conversion achieved at concentrations of 3 mM and 65 mM, respectively. The oxidizing agents affected the product distribution, influencing the type and selectivity of the CYP-catalyzed reaction. Additionally, CYP154C3s also catalyzed the C-C bond cleavage of steroids. Therefore, CYP154C3s may be a good candidate for the production of modified steroids for various biological uses.