Glycopeptides
Thomas T. Yoshikawa, Shobita Rajagopalan in Antibiotic Therapy for Geriatric Patients, 2005
Glycopeptides are chemically complex antimicrobial compounds that contain a heptapeptide connected to a variety of sugar groups. Vancomycin was isolated from Nocardia orientalis. Teicoplanin is derived from the Actinomycete, Actinoplanes teichomyceticus. Both vancomycin and teichoplanin were discovered in the 1950s. Vancomycin was introduced into clinical use in 1956, and since that time, teicoplanin has been used extensively in Europe but not in the United States. Glycopeptides have a larger structure and molecular weight than do β-lactams and aminoglycosides. Both vancomycin and teicoplanin act on the peptidoglycan component of bacterial cell walls in Gram-Positive Organisms. Vancomycin has an effect on intracellular or RNA synthesis, but teichoplanin does not. Pharmacokinetically, vancomycin and teicoplanin exhibit concentration-dependent killing kinetics and are bactericidal at high concentrations and are bacterostatic at lower concentrations (4-7).
Ramoplanin
M. Lindsay Grayson, Sara E. Cosgrove, Suzanne M. Crowe, M. Lindsay Grayson, William Hope, James S. McCarthy, John Mills, Johan W. Mouton, David L. Paterson in Kucers’ The Use of Antibiotics, 2017
Ramoplanin (A 16686, A 16686A, MDL 62198, NTI-851) is a novel oral nonabsorbable 17-amino-acid cyclic lipoglycodepsipeptide antibiotic from Biosearch Italia. Cyclic lipodepsipeptides (see Chapter 45, Daptomycin) contain one or more ester bonds along with the amide bonds and have emerged as promising candidates for the development of new antibiotics. Ramoplanin is an antibiotic complex first identified in 1984 that was isolated from the fermentation broth of Actinoplanes spp. ATCC 33076. It is a mixture of three closely related compounds, ramoplanin A1–A3, which differ only in the acyl group attached to the Asn-1 N-terminus; ramoplanin A2 is the most abundant (Shin et al., 2004). The empirical formula is C106H170ClN21O30, and the molecular weight is 2254. The chemical structure of ramoplanin is shown in Figure 49.1.
Biotransformation of Monoterpenoids by Microorganisms, Insects, and Mammals
K. Hüsnü Can Başer, Gerhard Buchbauer in Handbook of Essential Oils, 2020
As the microbial method for the formation of mosquito repellent 50a′ was established, the production of (+)-dihydrocarvone (101a′) and (+)-neodihydrocarveol (102a′) as the precursor of mosquito repellent 50a′ was investigated by using 40 strains of bacteria belonging to Escherichia, Aerobacter, Serratia, Proteus, Alcaligenes, Bacillus, Agrobacterium, Micrococcus, Staphylococcus, Corynebacterium, Sarcina, Arthrobacter, Brevibacterium, Pseudomonas, and Xanthomonas spp.; 68 strains of yeasts belonging to Schizosaccharomyces, Endomycopsis, Saccharomyces, Schwanniomyces, Debaryomyces, Pichia, Hansenula, Lipomyces, Torulopsis, Saccharomycodes, Cryptococcus, Kloeckera, Trigonopsis, Rhodotorula, Candida, and Trichosporon spp.; 40 strains of fungi belonging to Mucor, Absidia, Penicillium, Rhizopus, Aspergillus, Monascus, Fusarium, Pullularia, Keratinomyces, Oospora, Neurospora, Ustilago, Sporotrichum, Trichoderma, Gliocladium, and Phytophthora spp.; and 48 strains of actinomycetes belonging to Streptomyces, Actinoplanes, Nocardia, Micromonospora, Microbispora, Micropolyspora, Amorphosporangium, Thermopolyspora, Planomonospora, and Streptosporangium spp.
Reappraisal and perspectives of clinical drug–drug interaction potential of α-glucosidase inhibitors such as acarbose, voglibose and miglitol in the treatment of type 2 diabetes mellitus
Published in Xenobiotica, 2018
Ranjeet Prasad Dash, R. Jayachandra Babu, Nuggehally R. Srinivas
Among the aforementioned anti-diabetic drug categories, AGIs are considered an important therapeutic class, which consist of three drugs namely acarbose, voglibose and miglitol (Figure 1). However, it has not been rated high in the preference list for diabetes management, despite the fact of having comparable effect on glycated hemoglobin as that of metformin or thiazolidinediones (van de Laar, 2008). AGIs primarily belong to bacterial origin or the derivatives of their products. Acarbose was isolated from Actinoplanes; miglitol, a semisynthetic derivative of 1-deoxynojirimycin, from Bacillus and Streptomyces sp. and voglibose, is a semisynthetic derivative of validamycin A, obtained from Streptomyces hygroscopicus var. limoneus (Hanefeld & Schaper, 2007).
Current developments in lantibiotic discovery for treating Clostridium difficile infection
Published in Expert Opinion on Drug Discovery, 2019
Actagardine (originally isolated under the name of gardimycin) is produced by Actinoplanes garbadinensis and Actinoplanes liguriae [72]. Actagardine acts by binding to lipid II, blocking the transglycosylation reaction involved in cell wall synthesis, thus inhibiting the process [73]. Actagardine is a lantibiotic with antimicrobial activity against a range of Gram-positive bacteria, producing MICs in the range of 1.477–11.813 μg/ml against C. difficile [74]. Actagardine A is a naturally occurring variant containing an additional alanine that is produced by A. liguriae ATCC 31049 [75]. A variant library of actagardine A was generated through saturation mutagenesis. The potency of this lantibiotic was increased compared to the wild type peptide against C. difficile by virtue of the substitution phenylalanine to valine at position 15 (V15F) [76]. Additional investigation into this lantibiotic and the ability of bioengineering to enhance its properties is warranted.
Evaluation of a flavonoids library for inhibition of pancreatic α-amylase towards a structure–activity relationship
Published in Journal of Enzyme Inhibition and Medicinal Chemistry, 2019
Carina Proença, Marisa Freitas, Daniela Ribeiro, Sara M. Tomé, Eduardo F. T. Oliveira, Matilde F. Viegas, Alberto N. Araújo, Maria J. Ramos, Artur M. S. Silva, Pedro A. Fernandes, Eduarda Fernandes
Acarbose is a pseudotetrasaccharide produced by Actinoplanes sp. fermentation and its structure comprises a hydroxymethyl conduritol residue α-(1,4) linked to a 4-amino-4,6-dideoxyglucose which is, in turn, α-(1,4) linked to maltose52,53. It is the most widely prescribed α-glucosidase and α-amylase inhibitor. However, it was previously shown that only a mild inhibition of pancreatic α-amylase is recommended in order to avoid gastrointestinal side-effects as a result of excessive bacterial fermentation of carbohydrates in colon11, that has been shown as a limiting factor for T2DM treatment, in some countries11. In the present work, the IC50 values found for the tested flavonoids were higher than the IC50 value found for acarbose, which is 1.3 ± 0.2 µM. The mild pancreatic α-amylase inhibition prevents the abnormal bacterial fermentation of carbohydrates in the colon and consequent gastrointestinal adverse effects, such as abdominal distention, flatulence and diarrhea11. Moreover, it was previously shown by our research group that, in general, the tested flavonoids were more effective concerning the inhibition of α-glucosidase than the inhibition of α-amylase15. As such, the obtained results suggest that flavonoids could be promising α-amylase inhibitors and cause less gastrointestinal side-effects. Interestingly, it was found that the combination of baicalein or apigenin with acarbose showed additive inhibition of α-amylase at lower concentrations and antagonistic inhibition at higher concentrations. On the other hand, the combination of baicalein with acarbose synergistically inhibits α-glucosidase and lowers HGPP54.
Related Knowledge Centers
- Micromonosporaceae
- Valienamine
- Acarbose
- Validamycin
- Teicoplanin
- Ramoplanin
- Actinoplanes Abujensis
- Actinoplanes Atraurantiacus
- Actinoplanes Bogorensis
- Actinoplanes Capillaceus