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Jin Cheol Yoo - One of the best experts on this subject based on the ideXlab platform.
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Monoclonal antibody production and immunochemical detection of polyether antibiotics
Archives of Pharmacal Research, 2009Co-Authors: Hyo-jeong Lee, Jaya Ram Simkhada, Seung Sik Cho, Jin Cheol YooAbstract:Abstract Polyether antibiotics such as monensin and salinomycin have been primarily used as coccidiostat and growth promoter. Since residues of these antibiotic in food may pose a health risk for sensitive individuals, their use should be carefully monitored. An immunochemical method was developed for the determination of polyether antibiotic using monoclonal antibody (Mab) produced by immunized mice. Conjugates of monensin, salinomycin and Laidlomycin were prepared with bovine serum albumin (BSA), keyhole limpet haemocyanine (KLH) and ovalbumin (OVA) by mixed anhydride method and then used as immunogene to produce Mab. Eight hybridoma cell lines were isolated that produced Mabs that competed with polyether antibiotic-protein conjugates in BALB/c-SP2/0 fusion system. Two hybridoma with higher sensitivity, designated as 4G11F and 1C8F1F, were cultured for mass production and then purified from ascites fluid. Antibiotic-protein conjugates were quantitavely analyzed by using the purified Mabs through a competitive enzyme-linked immunosorbent assay (ELISA).
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production and biological activity of Laidlomycin anti mrsa vre antibiotic from streptomyces sp cs684
Journal of Microbiology, 2007Co-Authors: Jin Cheol Yoo, Jun Ho Kim, Nae Soo Park, Jae Kyung Sohng, June Woo Lee, Seong Chan Park, Mi Sun Kim, Chi Nam SeongAbstract:Culture broth of a streptomycete isolate, Streptomyces sp. CS684 showed antibacterial activity on methicillin resistant Staphylococcus aureus (MRSA) and vancomycin resistant enterococci (VRE). Among purified substances from the organism, CSU-1, which is active against MRSA and VRE, is a C37H62O12Na (M+, 721.3875), and identified as Laidlomycin. The anti-MRSA and anti-VRE activity of CSU-1 was stronger than oxacillin and vancomycin. Phylogenetic analysis showed that strain CS684 is very similar to Streptomyces ardus NRRL 2817T, whereas the ability of Streptomyces sp. CS684 to produce Laidlomycin was shown to be unique.
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Production and Biological Activity of Laidlomycin, Anti-MRSA/VRE Antibiotic from Streptomyces sp. CS684
Journal of microbiology (Seoul Korea), 2007Co-Authors: Jin Cheol Yoo, Jun Ho Kim, Nae Soo Park, Jae Kyung Sohng, June Woo Lee, Seong Chan Park, Mi Sun Kim, Chi Nam SeongAbstract:Culture broth of a streptomycete isolate, Streptomyces sp. CS684 showed antibacterial activity on methicillin resistant Staphylococcus aureus (MRSA) and vancomycin resistant enterococci (VRE). Among purified substances from the organism, CSU-1, which is active against MRSA and VRE, is a C37H62O12Na (M+, 721.3875), and identified as Laidlomycin. The anti-MRSA and anti-VRE activity of CSU-1 was stronger than oxacillin and vancomycin. Phylogenetic analysis showed that strain CS684 is very similar to Streptomyces ardus NRRL 2817T, whereas the ability of Streptomyces sp. CS684 to produce Laidlomycin was shown to be unique.
M L Galyean - One of the best experts on this subject based on the ideXlab platform.
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Effects of type of ionophore and carrier on in vitro ruminal dry matter disappearance, gas production, and fermentation end products of a concentrate substrate
Animal Feed Science and Technology, 2011Co-Authors: C.h. Ponce, D.r. Smith, M.e. Branine, M. E. Hubbert, M L GalyeanAbstract:Abstract Effects of ionophore type and carrier on in vitro ruminal digestion and fermentation patterns of a concentrate substrate were evaluated at various incubation times. Treatments were: control (no ionophore); lasalocid sodium commercial premix (Bov); lasalocid sodium mycelium cake (LasBio); Laidlomycin sodium salt (LaidNa); Laidlomycin propionate commercial premix (LaidPro); monensin sodium salt (Mon); and monensin sodium commercial premix (Rum). The Bov, LasBio, Mon, and Rum treatments supplied 4 μg of ionophore/mL of culture volume, whereas the LaidNa and LaidPro treatments supplied 1.33 μg of ionophore/mL. Total gas and methane production did not differ among treatments at any of the incubation times (P>0.09). Similarly, in vitro dry matter disappearance (IVDMD) was not affected by treatment (P>0.28) at 6, 18, and 24 h of incubation; however, IVDMD (P=0.03) was greater for ionophores than for the control at 12 h of incubation. Molar proportions of acetate (P vs . Laidlomycin; P vs . monensin; P vs . lasalocid or Laidlomycin; P
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effects of ionophores and antibiotics on in vitro hydrogen sulfide production dry matter disappearance and total gas production in cultures with a steam flaked corn based substrate with or without added sulfur
Journal of Animal Science, 2009Co-Authors: M.j. Quinn, N Dilorenzo, J Leibovich, D.r. Smith, K E Hales, M L GalyeanAbstract:: Effects of 3 ionophores and 2 antibiotics on in vitro H(2)S production, IVDMD, total gas production, and VFA profile with or without added S were examined. In Exp. 1, ruminal fluid from 2 ruminally cannulated steers fed a steam-flaked corn-based diet (75% concentrate) without ionophore and antibiotics for 28 d before collection was used to inoculate in vitro cultures. Treatments were control (no ionophore or antibiotic), 3 ionophores (lasalocid sodium and monensin sodium at 5 mg/L or Laidlomycin propionate at 1.65 mg/L), and 2 antibiotics (chlortetracycline hydrochloride at 5 mg/L and tylosin tartarate at 1.25 mg/L). Cultures also had 0 or 1.75 mg of S/L (from sodium sulfate). No S x ionophore-antibiotic treatment interactions were noted (P > 0.53) for IVDMD, total gas production, and H(2)S production. Hydrogen sulfide (mumol/g of fermentable DM) was increased (P 0.18). On average, IVDMD (P = 0.05) was greater for ionophores than for antibiotics, whereas total gas production was less for ionophores than for control (P 0.20) in acetate, propionate, or acetate:propionate between ionophores and control (S x treatment interaction, P = 0.03). In Exp. 2, the effects of ionophore-antibiotic combinations with added S were examined using the same procedures as in Exp. 1. Treatments were control, monensin plus tylosin (MT), and lasalocid plus chlortetracycline (LCTC), with concentrations of the ionophores and antibiotics as in Exp. 1. No differences were observed among treatments for H(2)S production (P > 0.55). Treatments MT and LCTC tended (P = 0.06) to increase IVDMD and decreased (P = 0.02) gas production vs. control. Proportion of acetate (P = 0.01) and acetate:propionate (P < 0.01) were decreased and propionate increased (P = 0.01) for both MT and LCTC compared with control. These data suggest that when S is approximately 0.42% of substrate DM, the 3 ionophores and 2 antibiotics we evaluated did not affect production of H(2)S gas in an in vitro rumen culture system.
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Performance of feedlot steers fed diets containing Laidlomycin propionate or monensin plus tylosin, and effects of Laidlomycin propionate concentration on intake patterns and ruminal fermentation in beef steers during adaptation to a high-concentrate
Journal of animal science, 1992Co-Authors: M L Galyean, K J Malcolm, Glenn C. DuffAbstract:Two hundred eighty-eight beef steers (British x Continental x Brahman) were fed a 90% concentrate diet containing either no ionophore (control), Laidlomycin propionate at either 6 or 12 mg/kg of dietary DM, or monensin plus tylosin (31 and 12 mg/kg of DM, respectively). Neither of the two levels of Laidlomycin propionate nor monensin plus tylosin affected (P greater than .10) ADG or feed:gain ratio. Monensin plus tylosin reduced (P less than .01) daily DMI for the 161-d trial period compared with the other three treatments. Laidlomycin propionate at 6 mg/kg increased (P less than .05) DMI relative to the control, Laidlomycin propionate at 12 mg/kg, and monensin plus tylosin diets during the 2nd wk of the trial and from d 57 to 84. Treatments did not affect carcass measurements. In a second experiment, 12 ruminally cannulated steers were fed diets containing no ionophore or Laidlomycin propionate at either 6 or 12 mg/kg of DM. Samples were obtained for two consecutive days while the dietary concentrate level was 75%, after which the diet was switched abruptly to 90% concentrate, and samples were collected on several days during a 21-d period. The rate at which steers consumed their daily allotment of feed was not altered markedly by Laidlomycin propionate. Likewise, Laidlomycin propionate did not affect total ruminal VFA concentrations or proportions. Ruminal concentrations of D-lactate were reduced (P less than .10) by 6 but not by 12 mg/kg of Laidlomycin propionate.(ABSTRACT TRUNCATED AT 250 WORDS)
Stanislav Pospisil - One of the best experts on this subject based on the ideXlab platform.
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negative ion fast atom bombardment tandem mass spectrometry of sodium salts of monensins and related compounds
Journal of Mass Spectrometry, 1995Co-Authors: Vladimir Havlicek, Miroslav Ryska, Stanislav PospisilAbstract:The negative-ion collisionally induced dissociation fast atom bombardment mass spectra of sodium salts of monensins A and B, their 3-O-demethyl derivatives, Laidlomycin and 26-deoxyLaidlomycin are reported. The nature of the R3 substituent appears to be important for the formation of sodium-containing product ions. Fragment ion series observed in the mass spectra of the [M − H]− ions of monensins are characterized by alkali metal retention. In contrast to monensins, the product ions observed in the corresponding spectra of Laidlomycins are sodium free. The affinity of monensins to alkali metals is a useful feature that may be used for the structure determination of unknown monensins, their metabolites and derivates. The structure of a novel natural monensin was elucidated based on its mass spectrometric behaviour.
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Negative‐ion fast atom bombardment tandem mass spectrometry of sodium salts of monensins and related compounds
Journal of Mass Spectrometry, 1995Co-Authors: Vladimir Havlicek, Miroslav Ryska, Stanislav PospisilAbstract:The negative-ion collisionally induced dissociation fast atom bombardment mass spectra of sodium salts of monensins A and B, their 3-O-demethyl derivatives, Laidlomycin and 26-deoxyLaidlomycin are reported. The nature of the R3 substituent appears to be important for the formation of sodium-containing product ions. Fragment ion series observed in the mass spectra of the [M − H]− ions of monensins are characterized by alkali metal retention. In contrast to monensins, the product ions observed in the corresponding spectra of Laidlomycins are sodium free. The affinity of monensins to alkali metals is a useful feature that may be used for the structure determination of unknown monensins, their metabolites and derivates. The structure of a novel natural monensin was elucidated based on its mass spectrometric behaviour.
Chi Nam Seong - One of the best experts on this subject based on the ideXlab platform.
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production and biological activity of Laidlomycin anti mrsa vre antibiotic from streptomyces sp cs684
Journal of Microbiology, 2007Co-Authors: Jin Cheol Yoo, Jun Ho Kim, Nae Soo Park, Jae Kyung Sohng, June Woo Lee, Seong Chan Park, Mi Sun Kim, Chi Nam SeongAbstract:Culture broth of a streptomycete isolate, Streptomyces sp. CS684 showed antibacterial activity on methicillin resistant Staphylococcus aureus (MRSA) and vancomycin resistant enterococci (VRE). Among purified substances from the organism, CSU-1, which is active against MRSA and VRE, is a C37H62O12Na (M+, 721.3875), and identified as Laidlomycin. The anti-MRSA and anti-VRE activity of CSU-1 was stronger than oxacillin and vancomycin. Phylogenetic analysis showed that strain CS684 is very similar to Streptomyces ardus NRRL 2817T, whereas the ability of Streptomyces sp. CS684 to produce Laidlomycin was shown to be unique.
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Production and Biological Activity of Laidlomycin, Anti-MRSA/VRE Antibiotic from Streptomyces sp. CS684
Journal of microbiology (Seoul Korea), 2007Co-Authors: Jin Cheol Yoo, Jun Ho Kim, Nae Soo Park, Jae Kyung Sohng, June Woo Lee, Seong Chan Park, Mi Sun Kim, Chi Nam SeongAbstract:Culture broth of a streptomycete isolate, Streptomyces sp. CS684 showed antibacterial activity on methicillin resistant Staphylococcus aureus (MRSA) and vancomycin resistant enterococci (VRE). Among purified substances from the organism, CSU-1, which is active against MRSA and VRE, is a C37H62O12Na (M+, 721.3875), and identified as Laidlomycin. The anti-MRSA and anti-VRE activity of CSU-1 was stronger than oxacillin and vancomycin. Phylogenetic analysis showed that strain CS684 is very similar to Streptomyces ardus NRRL 2817T, whereas the ability of Streptomyces sp. CS684 to produce Laidlomycin was shown to be unique.
Sung-ho Kang - One of the best experts on this subject based on the ideXlab platform.
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Total synthesis of Laidlomycin
Chemical communications (Cambridge England), 2016Co-Authors: Won-chul Lee, Sungkyoung Kang, Byunghyuck Jung, Hee-seung Lee, Sung-ho KangAbstract:The synthesis of Laidlomycin is described. With an established stereocontrolled synthetic route to the aldehyde 5, the known β-keto phosphonate 4 was coupled with 5 and the resulting enone was subjected to a sequential hydrogenolysis/hydrogenation and equilibration process to effect the correct spiroketalization for the natural product. The stereogenic carbons were elaborated by desymmetrization for C12, allylation for C13, vanadyl-induced epoxidation for C16, Zn(BH4)2 reduction for C17, a chiral building block for C18 and C24, Shi epoxidation for C20 and C21, Myers’ alkylation for C22, and thermodynamic control for C25.
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Stereocontrolled Synthesis of the C1-C10 Fragments of Monensin B and Laidlomycin
Asian Journal of Organic Chemistry, 2015Co-Authors: Sungkyoung Kang, Byunghyuck Jung, Sung-ho KangAbstract:An efficient synthetic route to the C1-C10 fragments of Laidlomycin and monensin B has been developed toward their total synthesis. The asymmetric carbons have been elaborated by a syn-aldol reaction using the oxazolidinone chiral auxiliary for C6 and C7, an anti-aldol reaction for C3 and C4, the Tishchenko–Evans reaction for C5, and a chiral building block for C2.
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Stereocontrolled Synthesis of the C1‐C10 Fragments of Monensin B and Laidlomycin
Asian Journal of Organic Chemistry, 2015Co-Authors: Sungkyoung Kang, Byunghyuck Jung, Won-chul Lee, Hee-seung Lee, Sung-ho KangAbstract:An efficient synthetic route to the C1-C10 fragments of Laidlomycin and monensin B has been developed toward their total synthesis. The asymmetric carbons have been elaborated by a syn-aldol reaction using the oxazolidinone chiral auxiliary for C6 and C7, an anti-aldol reaction for C3 and C4, the Tishchenko–Evans reaction for C5, and a chiral building block for C2.
