Lincomycin
Erythromycin
Carbadox
Drug Resistance, Microbial
Leucomycins
Encyclopedias as Topic
Streptomyces
Streptomyces coelicolor
Injections, Intramuscular
Lincosamides
A new resistance gene, linB, conferring resistance to lincosamides by nucleotidylation in Enterococcus faecium HM1025. (1/221)
Resistance to lincomycin and clindamycin in the clinical isolate Enterococcus faecium HM1025 is due to a ribosomal methylase encoded by an ermAM-like gene and the plasmid-mediated inactivation of these antibiotics. We have cloned and determined the nucleotide sequence of the gene responsible for the inactivation of lincosamides, linB. This gene encodes a 267-amino-acid lincosamide nucleotidyltransferase. The enzyme catalyzes 3(5'-adenylation) (the adenylation of the hydroxyl group in position 3 of the molecules) of lincomycin and clindamycin. Expression of linB was observed in both Escherichia coli and Staphylococcus aureus. The deduced amino acid sequence of the enzyme did not display any significant homology with staphylococcal nucleotidyltransferases encoded by linA and linA' genes. Sequences homologous to linB were found in 14 other clinical isolates of E. faecium, indicating the spread of the resistance trait in this species. (+info)Inducible or constitutive expression of resistance in clinical isolates of streptococci and enterococci cross-resistant to erythromycin and lincomycin. (2/221)
Thirty-five of 40 clinical isolates of enterococci and streptococci cross-resistant to erythromycin and lincomycin and harbouring erm genes were inducibly resistant to these drugs, suggesting that ribosomal methylation is predominantly inducibly expressed in these bacterial genera. Regulatory regions located upstream of the erm genes of four inducible and three constitutive strains were amplified and sequenced. Expression of constitutive resistance in two strains of Streptococcus pneumoniae and Enterococcus faecalis could be accounted for by a large deletion or a DNA duplication within the regulatory regions, respectively. (+info)Variation in the properties of a strain of Staphylococcus aureus isolated over three months from a single hospital. (3/221)
A strain of Staphylococcus aureus has been isolated from a hospital environment over 3 months. Every isolate was lysed by phage 77, had high-level resistance to streptomycin, and was resistant to about 250 pg per ml of both tetracycline and sulphonamide; a combination of sulphamethoxazole and trimethoprim produced little bacteristatic synergy towards each isolate. All These organisms were thus considered to be "the same"; the variation in other properties was probably due to rapid evolutionary change in vivo. the variation in senxitivity to methicillin and neomycin, and the absence of penicillinase production in some isolates, probably indicated loss of the relevant genes. Several isolates had probably acquired resistance to lincomycin by a one-step mutatuon in vivo. The usefulness of lincomycin and analogues in treating staphylococcal infections seems limited. (+info)Further evolution of a strain of Staphylococcus aureus in vivo: evidence for significant inactivation of flucloxacillin by penicillinase. (4/221)
A strain of Staphylococcus aureus (no. FAR4) has been isolated at intervals, for 32 months, from the sputum of a patient with cystic fibrosis of the lung. Changes in the properties of isolates of this strain over the first 18 months have been reported previously (Lacey et al., 1973 and 1974). During the last 14 months (May 1973 to July 1974), further evolution has occurred to produce a total of 31 distinct phenotypes. Recent changes are as follows. 1. The ability of isolates to produce penicillinase in vitro was closely correlated with flucloxacillin therapy. Inactivation of flucloxacillin by penicillinase was demonstrated by diffusion testing (but not MIC determination) in vitro and may have occurred to a significant extent in vivo. 2. Lincomycin-resistant mutants slowly disappeared from the sputum after the termination of clindamycin therapy. 3. All of the recent isolates were resistant to erythromycin, possibly because of the linkage of the genes coding for erythromycin resistance with those coding for the production of delta-haemolysin; delta-haemolysin may be an important "virulence factor". (+info)Transfer of plasmid-mediated antibiotic resistance from streptococci to lactobacilli. (5/221)
The transmissible plasmid pAMbeta1, which codes for erythromycin and lincomycin resistance, was conjugally transferred from a Lancefield group F Streptococcus to a strain of Streptococcus avium. Both organisms served as pAMbeta1 donors for three strains of Lactobacillus casei. Introduction of pAMbeta1 into one of the L. casei strains caused the organism to lose its native 6.7 X 10(6)-dalton plasmid. Loss of the native plasmid produced no alterations in the organism's growth characteristics or fermentation pattern. (+info)Antibiotic susceptibilities of streptococci from the mouth and blood of patients treated with penicillin or lincomycin and clindamycin. (6/221)
Patients undergoing dental extractions were non-randomly allocated to three groups, one of which received no antibiotic, one benzylpenicillin followed by oral penicillin for 5 days, and the third intramuscular lincomycin followed by oral clindamycin. Dental extraction was performed at the beginning of the course of chemotherapy. Streptococci were isolated from the extracted teeth, from blood cultures collected before and immediately after dental extraction, and from sutures removed from the gums 5-7 days after the operation. The species of these organisms was determined, and their susceptibilities to penicillin, clindamycin, cephaloridine, erythromycin and tetracycline were assessed. The majority of streptococci isolated from teeth belonged to the species Streptococcus sanguis, S. mitior, S. mutans and S. milleri. Occasional isolates of each of these organisms collected before the antibiotic could take effect were resistant to penicillin. Three of these species, but not S. mutans, were the commonest streptococci to be isolated from the blood after dental extraction. Penicillin completely suppressed dental bacteriaemia under the conditions of our investigation, and lincomycin reduced the incidence by about 60 per cent. The commonest streptococci from sutures were also S. sanguis, S. mitior, S. mutans and S. milleri. S. faecalis was also isolated, but only in patients who had received antibiotics. Among the non-faecalis organisms, penicillin resistance was significantly more frequent among isolates from patients given penicillin than from patients not given this antibiotic, and clindamycin resistance was significantly more frequent among isolates from patients given lincomycin and clindamycin than from patients not given these antibiotics. (+info)Slow sequential conformational changes in Escherichia coli ribosomes induced by lincomycin: kinetic evidence. (7/221)
In a cell-free system derived from Escherichia coli, lincomycin produces biphasic logarithmic time plots for inhibition of peptide-bond formation when puromycin is used as an acceptor substrate and AcPhe-tRNA as a donor substrate. In a previous study, initial slope analysis of the logarithmic time plots revealed that the encounter complex CI between the initiator ribosomal complex (C) and lincomycin (I) undergoes a slow isomerization to C*I. During this change, the bound AcPhe-tRNA and lincomycin are rearranged to also accommodate puromycin, and this may account for the mixed noncompetitive inhibition (K(i)* = 70 microM) established at higher concentrations of the drug. The above-mentioned effect was further investigated by analyzing the late phase of the logarithmic time plots. It was found that C*I complex reacts with a second molecule of I, giving C*I(2) complex. However, the logarithmic time plots remain biphasic even at high concentrations of lincomycin, making possible the identification of another inhibition constant K(i)*', which is equal to 18 microM. The simplest explanation of this finding is to assume the existence of a second isomerization step C*I(2) <--> C*I(2'), slowly equilibrated. The determination of K(i)*' enables us to calculate the isomerization constant (K(isom) = 2.9) with the formula K(i)*' = K(i)*/(1 + K(isom)). Our results suggest that whenever a fast and reversible interaction of lincomycin with the elongating ribosomal complex C occurs, the latter undergoes a slow isomerization, which may be the result of conformational changes induced by the drug. (+info)Characterization of a Bacteroides mobilizable transposon, NBU2, which carries a functional lincomycin resistance gene. (8/221)
The mobilizable Bacteroides element NBU2 (11 kbp) was found originally in two Bacteroides clinical isolates, Bacteroides fragilis ERL and B. thetaiotaomicron DOT. At first, NBU2 appeared to be very similar to another mobilizable Bacteroides element, NBU1, in a 2.5-kbp internal region, but further examination of the full DNA sequence of NBU2 now reveals that the region of near identity between NBU1 and NBU2 is limited to this small region and that, outside this region, there is little sequence similarity between the two elements. The integrase gene of NBU2, intN2, was located at one end of the element. This gene was necessary and sufficient for the integration of NBU2. The integrase of NBU2 has the conserved amino acids (R-H-R-Y) in the C-terminal end that are found in members of the lambda family of site-specific integrases. This was also the only region in which the NBU1 and NBU2 integrases shared any similarity (28% amino acid sequence identity and 49% sequence similarity). Integration of NBU2 was site specific in Bacteroides species. Integration occurred in two primary sites in B. thetaiotaomicron. Both of these sites were located in the 3' end of a serine-tRNA gene NBU2 also integrated in Escherichia coli, but integration was much less site specific than in B. thetaiotaomicron. Analysis of the sequence of NBU2 revealed two potential antibiotic resistance genes. The amino acid sequences of the putative proteins encoded by these genes had similarity to resistances found in gram-positive bacteria. Only one of these genes was expressed in B. thetaiotaomicron, the homolog of linA, a lincomycin resistance gene from Staphylococcus aureus. To determine how widespread elements related to NBU1 and NBU2 are in Bacteroides species, we screened 291 Bacteroides strains. Elements with some sequence similarity to NBU2 and NBU1 were widespread in Bacteroides strains, and the presence of linA(N) in Bacteroides strains was highly correlated with the presence of NBU2, suggesting that NBU2 has been responsible for the spread of this gene among Bacteroides strains. Our results suggest that the NBU-related elements form a large and heterogeneous family, whose members have similar integration mechanisms but have different target sites and differ in whether they carry resistance genes. (+info)Lincomycin is defined as an antibiotic produced by Streptomyces lincolnensis. It is primarily bacteriostatic, inhibiting protein synthesis in sensitive bacteria by binding to the 50S ribosomal subunit. Lincomycin is used clinically to treat a variety of infections caused by susceptible gram-positive organisms, including some anaerobes. It has activity against many strains of streptococci, pneumococci, and staphylococci, but not enterococci. Common side effects include gastrointestinal symptoms such as nausea, vomiting, and diarrhea.
Clindamycin is a antibiotic medication used to treat a variety of bacterial infections. It is a type of antibiotic known as a lincosamide, which works by binding to the bacterial ribosome and inhibiting protein synthesis. This leads to the death of the bacteria and helps to clear the infection.
Clindamycin is effective against a wide range of gram-positive and some anaerobic bacteria, making it a useful antibiotic for treating many different types of infections, including skin and soft tissue infections, bone and joint infections, respiratory infections, and dental infections. It is also sometimes used to treat certain types of bacterial vaginal infections.
Like all antibiotics, clindamycin should be used only under the direction of a healthcare provider, as misuse can lead to antibiotic resistance. Additionally, clindamycin can cause side effects such as diarrhea, nausea, and vomiting, and it may increase the risk of developing a serious intestinal infection called Clostridioides difficile-associated diarrhea (CDAD). It is important to follow your healthcare provider's instructions carefully when taking this medication.
Erythromycin is a type of antibiotic known as a macrolide, which is used to treat various types of bacterial infections. It works by inhibiting the bacteria's ability to produce proteins, which are necessary for the bacteria to survive and multiply. Erythromycin is often used to treat respiratory tract infections, skin infections, and sexually transmitted diseases. It may also be used to prevent endocarditis (inflammation of the lining of the heart) in people at risk of this condition.
Erythromycin is generally considered safe for most people, but it can cause side effects such as nausea, vomiting, and diarrhea. It may also interact with other medications, so it's important to tell your doctor about all the drugs you are taking before starting erythromycin.
Like all antibiotics, erythromycin should only be used to treat bacterial infections, as it is not effective against viral infections such as the common cold or flu. Overuse of antibiotics can lead to antibiotic resistance, which makes it harder to treat infections in the future.
Anti-bacterial agents, also known as antibiotics, are a type of medication used to treat infections caused by bacteria. These agents work by either killing the bacteria or inhibiting their growth and reproduction. There are several different classes of anti-bacterial agents, including penicillins, cephalosporins, fluoroquinolones, macrolides, and tetracyclines, among others. Each class of antibiotic has a specific mechanism of action and is used to treat certain types of bacterial infections. It's important to note that anti-bacterial agents are not effective against viral infections, such as the common cold or flu. Misuse and overuse of antibiotics can lead to antibiotic resistance, which is a significant global health concern.
Ronidazole is an antiprotozoal and antibacterial medication. It is primarily used to treat infections caused by susceptible anaerobic bacteria and protozoa, including certain types of diarrhea, bacterial vaginosis, and amebiasis. Ronidazole works by interfering with the DNA of the microorganisms, which leads to their death.
The medical definition of Ronidazole is: "A nitroimidazole antimicrobial agent used in the treatment of infections caused by susceptible anaerobic bacteria and protozoa, including Trichomonas vaginalis, Giardia lamblia, Entamoeba histolytica, and certain anaerobic bacteria."
It is important to note that Ronidazole has potential side effects, such as nausea, vomiting, headache, and a metallic taste in the mouth. In rare cases, it can cause more serious side effects, including peripheral neuropathy and seizures. It should be used with caution and under the supervision of a healthcare professional.
Treponemal infections are a group of diseases caused by the spirochete bacterium Treponema pallidum. This includes syphilis, yaws, bejel, and pinta. These infections can affect various organ systems in the body and can have serious consequences if left untreated.
1. Syphilis: A sexually transmitted infection that can also be passed from mother to fetus during pregnancy or childbirth. It is characterized by sores (chancres) on the genitals, anus, or mouth, followed by a rash and flu-like symptoms. If left untreated, it can lead to serious complications such as damage to the heart, brain, and nervous system.
2. Yaws: A tropical infection that is spread through direct contact with infected skin lesions. It primarily affects children in rural areas of Africa, Asia, and South America. The initial symptom is a painless bump on the skin that eventually ulcerates and heals, leaving a scar. If left untreated, it can lead to disfigurement and destruction of bone and cartilage.
3. Bejel: Also known as endemic syphilis, this infection is spread through direct contact with infected saliva or mucous membranes. It primarily affects children in dry and arid regions of Africa, the Middle East, and Asia. The initial symptom is a painless sore on the mouth or skin, followed by a rash and other symptoms similar to syphilis.
4. Pinta: A tropical infection that is spread through direct contact with infected skin lesions. It primarily affects people in rural areas of Central and South America. The initial symptom is a red or brown spot on the skin, which eventually turns into a scaly rash. If left untreated, it can lead to disfigurement and destruction of pigmentation in the skin.
Treponemal infections can be diagnosed through blood tests that detect antibodies against Treponema pallidum. Treatment typically involves antibiotics such as penicillin, which can cure the infection if caught early enough. However, untreated treponemal infections can lead to serious health complications and even death.
Carbadox is a veterinary drug that belongs to the class of medications called antimicrobials. It is specifically an antimicrobial agent with both antibacterial and coccidiostat properties. Carbadox is used in the treatment and prevention of certain bacterial infections in swine (pigs). It works by inhibiting the growth of bacteria and killing coccidia, a type of parasite that can cause infection in pigs.
Carbadox is available as a feed additive and is typically administered to pigs through their food. It is important to note that carbadox is not approved for use in animals destined for human consumption in many countries, including the European Union, due to concerns about potential carcinogenicity and other safety issues.
It's worth mentioning that the use of carbadox in food-producing animals has been a topic of controversy and debate in recent years, with some experts calling for stricter regulations or a complete ban on its use due to concerns about antibiotic resistance and human health.
Microbial drug resistance is a significant medical issue that refers to the ability of microorganisms (such as bacteria, viruses, fungi, or parasites) to withstand or survive exposure to drugs or medications designed to kill them or limit their growth. This phenomenon has become a major global health concern, particularly in the context of bacterial infections, where it is also known as antibiotic resistance.
Drug resistance arises due to genetic changes in microorganisms that enable them to modify or bypass the effects of antimicrobial agents. These genetic alterations can be caused by mutations or the acquisition of resistance genes through horizontal gene transfer. The resistant microbes then replicate and multiply, forming populations that are increasingly difficult to eradicate with conventional treatments.
The consequences of drug-resistant infections include increased morbidity, mortality, healthcare costs, and the potential for widespread outbreaks. Factors contributing to the emergence and spread of microbial drug resistance include the overuse or misuse of antimicrobials, poor infection control practices, and inadequate surveillance systems.
To address this challenge, it is crucial to promote prudent antibiotic use, strengthen infection prevention and control measures, develop new antimicrobial agents, and invest in research to better understand the mechanisms underlying drug resistance.
Leucomycins are a type of antibiotic produced by the bacterium Streptomyces kitasatoensis. They are known to be effective against a wide range of gram-positive bacteria, including some that are resistant to other antibiotics. Leucomycins belong to a class of antibiotics called aminoglycosides, which work by binding to the bacterial ribosome and inhibiting protein synthesis.
Leucomycin A, one of the components of leucomycins, has been studied for its potential anti-tumor properties. However, its use as a therapeutic agent is limited due to its toxicity and potential for causing hearing loss and kidney damage. Therefore, it is mainly used in research settings to study bacterial physiology and antibiotic resistance mechanisms.
An encyclopedia is a comprehensive reference work containing articles on various topics, usually arranged in alphabetical order. In the context of medicine, a medical encyclopedia is a collection of articles that provide information about a wide range of medical topics, including diseases and conditions, treatments, tests, procedures, and anatomy and physiology. Medical encyclopedias may be published in print or electronic formats and are often used as a starting point for researching medical topics. They can provide reliable and accurate information on medical subjects, making them useful resources for healthcare professionals, students, and patients alike. Some well-known examples of medical encyclopedias include the Merck Manual and the Stedman's Medical Dictionary.
Streptomyces is a genus of Gram-positive, aerobic, saprophytic bacteria that are widely distributed in soil, water, and decaying organic matter. They are known for their complex morphology, forming branching filaments called hyphae that can differentiate into long chains of spores.
Streptomyces species are particularly notable for their ability to produce a wide variety of bioactive secondary metabolites, including antibiotics, antifungals, and other therapeutic compounds. In fact, many important antibiotics such as streptomycin, neomycin, tetracycline, and erythromycin are derived from Streptomyces species.
Because of their industrial importance in the production of antibiotics and other bioactive compounds, Streptomyces have been extensively studied and are considered model organisms for the study of bacterial genetics, biochemistry, and ecology.
"Streptomyces coelicolor" is a species name for a type of bacteria that belongs to the genus Streptomyces. This bacterium is gram-positive, meaning that it stains positive in the Gram stain test, which is used to classify bacteria based on their cell wall structure. It is an aerobic organism, which means it requires oxygen to grow and survive.
Streptomyces coelicolor is known for its ability to produce a variety of antibiotics, including actinomycin and undecylprodigiosin. These antibiotics have been studied for their potential therapeutic uses in medicine. The bacterium also produces a blue-pigmented compound called pigmentactinorhodin, which it uses to protect itself from other microorganisms.
Streptomyces coelicolor is widely used as a model organism in research due to its genetic tractability and its ability to produce a diverse array of secondary metabolites. Scientists study the genetics, biochemistry, and ecology of this bacterium to better understand how it produces antibiotics and other bioactive compounds, and how these processes can be harnessed for industrial and medical applications.
"Intramuscular injections" refer to a medical procedure where a medication or vaccine is administered directly into the muscle tissue. This is typically done using a hypodermic needle and syringe, and the injection is usually given into one of the large muscles in the body, such as the deltoid (shoulder), vastus lateralis (thigh), or ventrogluteal (buttock) muscles.
Intramuscular injections are used for a variety of reasons, including to deliver medications that need to be absorbed slowly over time, to bypass stomach acid and improve absorption, or to ensure that the medication reaches the bloodstream quickly and directly. Common examples of medications delivered via intramuscular injection include certain vaccines, antibiotics, and pain relievers.
It is important to follow proper technique when administering intramuscular injections to minimize pain and reduce the risk of complications such as infection or injury to surrounding tissues. Proper site selection, needle length and gauge, and injection technique are all critical factors in ensuring a safe and effective intramuscular injection.
Lincosamides are a class of antibiotics that are structurally related to limcosamine and consist of lincomycin and its derivatives such as clindamycin. They bind to the 50S ribosomal subunit and inhibit bacterial protein synthesis. These antibiotics have a bacteriostatic effect and are primarily used to treat anaerobic infections, as well as some Gram-positive bacterial infections. Common side effects include gastrointestinal symptoms such as diarrhea and nausea. Additionally, lincosamides can cause pseudomembranous colitis, a potentially serious condition caused by the overgrowth of Clostridium difficile bacteria in the gut.