• Natural Product Sciences
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• v.4 no.2
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• pp.62-67
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• 1998

As a part of search for new biologically active constituents from aloe, we have isolated a glycopeptide, called G1G1M1DI2, from the gel(G1) of Aloe vera. Chemical and spectroscopic evidence indicated that G1G1M1DI2 is a glycopeptide. The molecular weight of G1G1M1DI2 was about 5,500 daltons, and the carbohydrate and protein contents were 20.9% and 32.6%, respectively. Periodate oxidation and enzymic degradation gave peptide moiety and carbohydrate moiety, respectively. Carbohydrate moiety is composed of fucose, galactose, glucose and mannose in a molar ratio of 0.5:2.4;48.8:48.3. Peptide moiety is composed of fifteen amino acids, and glutamic acid and glycine were the major componants. The glycopeptide, G1G1M1DI2, stimulated thymidine uptake of SCC 13 cells about 6.5 times the control. This result suggests that this glycopeptide has a skin cell proliferating activity.

• Proceedings of the Microbiological Society of Korea Conference
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• 2005.05a
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• pp.143-147
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• 2005

The non-pathogenic, non-glycopeptide-producing actinomycete Streptomyces coelicolor carries a cluster of seven genes (vanSRJKHAX) that confers inducible, high-level resistance to vancomycin. The van genes are organised into four transcription units, vanRS, vanJ, vanK and vanHAX, and these transcripts are induced by vancomycin in a vanR-dependent manner. vanHAX are orthologuous to genes found in vancomycin resistant enterococci that encode enzymes predicted to reprogramme peptidoglycan biosynthesis such that cell wall precursors terminate in D-Ala-D-Lac, rather than D-Ala-D-Ala. vanR and vanS encode a two-component signal transduction system that mediates transcriptional induction of the seven van genes. vanJ and vanK are novel genes that have no counterpart in previously characterised vancomycin-resistance clusters from pathogens. VanK is essential for vancomycin resistance in S. coelicolor and it is required for adding Gly branch to stem peptides terminating D-Ala-D-Lac. Because VanK can recognise D-Lac-containing precursors but the constitutively expressed femX enzyme, encoded elsewhere on the chromosome, cannot recognize D-Lac-containing precursors as a substrate, vancomycin-induced expression of VanHAX in a vanK mutant is lethal. Further, femX null mutants are viable in the presence of glycopeptide antibiotics but die in their absence. Bioassay using vanJp-neo fusion reporter system also showed that all identified inducers for van genes expression were glycopeptide antibiotics, but teicoplanin, a membrane-anchored glycopeptide, failed to act as an inducer.

• Bulletin of the Korean Chemical Society
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• v.33 no.11
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• pp.3565-3570
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• 2012

Until now, few groups reported the antifreeze activity of cyclic glycopeptides; however, the tedious synthetic procedure is not amenable to study the intensive structure activity relationship. A series of N-linked cyclic glycopeptoids and glycopeptide have been prepared to evaluate antifreeze activity as a function of peptide backbone cyclization and methyl stereochemical effect on the rigid Thr position. This study has combined the cyclization protocol with solid phase peptide synthesis and obtained significant quantities of homogeneous cyclic glycopeptide and glycopeptoids. Analysis of antifreeze activity revealed that our cyclic peptide demonstrated RI activity while cyclic glycopeptoids showed no RI activity. These results suggest that the subtle changes in conformation and Thr orientation dramatically influence RI activity of N-linked glycopeptoids.

• Journal of the Korean Chemical Society
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• v.48 no.2
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• pp.211-214
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• 2004

• Quality Improvement in Health Care
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• v.3 no.2
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• pp.26-35
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• 1997

Background : Glycopeptide antibiotics are the only drugs for treatment of infections due to beta-lactam-resistant Gram-positive bacteria. As the incidence of infection and colonization with vancomycin-resistant enterococci(VRE) rapidly increases, the hospital infection control practices advisory committee(HICPAC) recommends prudent vancomycin use to detect, prevent and control infection and colonization with VRE. Methods : The inpatients admitted from September to December, 1996 in Pusan National University Hospital, with Gram-positive bacterial infections were evaluated retrospectively to see whether the administrations of glycopeptide antibiotics were appropriate or not, upon comparison with the recommendations for preventing the spread of vancomycin resistance by HICPAC. Results : Teicoplanin has been chosen more frequently than vancomycin of the glycopeptide antibiotics. The indications of administration of glycopeptides in patients with pneumonia, wound infections, sepsis, and in febrile or neutropenic patients with malignancies were appropriate, but the use of glycopeptides for elimination of merely colonized bacteria in the oral cavity could not be excluded. Inappropriate use of glycopeptides was 10.6%, and inappropriately long-term use without positive culture for beta-lactam-resistant Gram-positive organisms was about 40% of total days of drug use. Conclusion : It seems essential for the quality assurance committee to make a plan in teaching the HICPAC recommendations to the medical practitioners who prescribed the glycopeptides inappropriately or used for irrelevantly long to his patient, monitor and survey their use of glycopeptides prospectively and periodically, and if there are repeated inappropriate prescriptions, a certain penalty would be given to the practitioners.

• Bioindustry News
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• v.11 no.2
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• pp.28-36
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• 1998

• Mass Spectrometry Letters
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• v.8 no.4
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• pp.69-78
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• 2017

Glycosylation, which is one of the most common post-translation modification (PTMs) of proteins, plays a variety of crucial roles in many cellular events and biotherapeutics. Recent advances have led to the development of various analytical methods employing a mass spectrometry for glycomic and glycoproteomic study. However, site-specific glycosylation analysis is still a relatively new area with high potential for technologies and method development. This review will cover current MS-based workflows and technologies for site-specific mapping of glycosylation ranging from glycopeptide preparation to MS analysis. Bioinformatic tools for comprehensive analysis of glycoprotein with high-throughput manner will be also included.

• Quality Improvement in Health Care
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• v.19 no.1
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• pp.30-42
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• 2013

Objectives: This study was intended to check if the "Creating Clean Wards" project, which is an innovative reinforced campaign activity targeting infection control strategies and active surveillance cultures for VRE (vancomycin resistant enterococci) high-risk patients to be admitted in the NS (neuro-surgery) wards, would be reduced the incidence rates of VRE acquisition, transmission rates. Methods: 75 subjects of the VRE high-risk patients were surveyed by carrying out active surveillance cultures of VRE colonization 11 times from January to March, 2012. And the retrospective study was conducted dividing them into two groups. Results: The incidence rates of VRE acquisition was reduced to 3.67 cases per 1,000 patients day in the control group and to 2.88 cases in experimental group, which was not statistically significant (p = .753). VRE transmission rates of 0.0015 per day before the project tended to increase to 0.0019, although not statistically significant (p = .650). As a result of multivariate analysis with regard to using glycopeptide antibiotics in order to find out risk factors of VRE colonization, the patients who had been treated with glycopeptide until VRE colonization showed 274.41 times higher rate. Conclusion : For effective VRE infection control in NS wards, We should carry out active surveillance culture regularly, especially patient of using glycopeptide. And block the spread of VRE by strengthening infection control through the strict isolation and the changed mind-set of members motivated by the "Creating Clean Wards" campaign.

• Bulletin of the Korean Chemical Society
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• v.23 no.1
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• pp.15-16
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• 2002

• Journal of Microbiology and Biotechnology
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• v.14 no.3
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• pp.612-619
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• 2004

A competitive direct enzyme-linked immunosorbent assay (cdELISA) was developed for selective and rapid detection of a glycopeptide antibiotic, teicoplanin (TP). TP was conjugated to bovine serum albumin (BSA) for use as an immunogen. Repeated subcutaneous injections of 0.5 mg of the conjugate was effective in generating specific polyclonal antibody (PAb) toward TP in rabbits, as determined by cdELISA. TP-horseradish peroxidase conjugate (TP-HRP) was used as an enzyme marker. The cdELISA was developed based on a competition reaction between TP-BSA PAb and TP-HRP conjugate. The TP-BSA PAb was highly sensitive (detection limit, 0.3 ng/ml and specific toward teicoplanin, showing no cross-reactivity to other glycopeptide antibiotics including vancomycin. There were good correlations ($r^2$=0.84 and 0.76, respectively) between cdELISA and microbiological assay, and high-performance liquid chromatography. The cdELISA system developed in this work is expected to be useful not only for selective and rapid monitoring of TP but also for study of TP pharmacokinetics.