エリスロマイシン

外観

白色の粉末

溶解性

エタノールに極めて易溶:アセトン、クロロホルム、アセトニトリル、酢酸エチルに易溶:エーテル、塩化エチレン、酢酸アミルに微溶:水には2mg/ml溶ける。エタノール及びアセトンに溶けやすく、水に極めて溶けにくい。

解説

C37H67NO13(733.93)．Streptomyces erythreusが産生する十四員環マクロライド抗生物質．水和物は白色の結晶．融点135～140 ℃．固化後，再融点190～193 ℃．[α]²⁵_D－78°(エタノール)．エタノール，アセトンに易溶，水に不溶．グラム陽性菌，グラム陰性菌，マイコプラズマ，クラミジアなどに抗菌力を示す．リボソームの50Sサブユニットに作用してタンパク質合成を阻害する．エリスロマイシンは，経口や外用薬で用いる。熔点135-148℃。在此温度下熔化后，在190-193℃下再次凝固和熔化。易溶于丙酮和氯仿。对支原体肺炎非常有效。副作用包括呕吐和腹泻。LD50 2580 mg/kg(マウス，経口)．森北出版「化学辞典（第2版）

用途

薬理研究用、培地添加用。

用途

マクロライド系抗生物質です。 細菌リボソーム 50s に結合し、タンパク質合 成阻害作用を示します。グラム陽性・陰性菌 に抗菌作用を示します。

用途

エリスロマイシン (erythromycin) はマクロライド系抗生物質の1つである。製品名は「エリスロシン®」(マイランEPD合同会社製造販売)。抗菌スペクトルはペニシリンと類似するが若干幅広く、ペニシリンにアレルギーを持つ人に対してしばしば使用される。呼吸器系への感染症に関しては、マイコプラズマ?クラミドフィラなどの非定型微生物に対しても高い効果を持つが、市中肺炎の原因菌の一つであるインフルエンザ菌には抗菌活性を示さない。

用途

放線菌の一種 Streptomyces erytheusが生産する抗生物質。マクロライド系抗生物質に属し，水から含水結晶を得る。主としてグラム陽性菌のほかスピロヘータおよびリケッチアの発育も阻止し，下記の感染症に有効で，特にペニシリン，テトラサイクリンなどに耐性を有する菌感染症に有用である。エリスロマイシンは，敗血症，骨髄炎，腎盂(じんう)炎，肺炎，リンパ節炎，扁桃炎，産褥(さんじょく)熱，猩紅(しょうこう)熱，ジフテリア，結膜炎，角膜炎，梅毒などに使用する。過敏症，消化器障害，時に難聴などの副作用も現れる。1952年米国のJ.M.マクガイアが発表。商品名アイロタイシン。

効能

抗生物質, タンパク質合成阻害薬

説明

Erythromycin ethyl succinate is a mixed double ester pro-drug in which one carboxyl of succinic acid esterifies the C-2′ hydroxyl of erythromycin and the other ethanol. This pro-drug frequently is used in an oral suspension for pediatric use largely to mask the bitter taste of the drug. Film-coated tablets also are used to deal with this. Some cholestatic jaundice is associated with the use of EES.

化学的特性

White to off white crystalline powder

使用

Erythromycin A is a 14-membered macrocyclic lactone with broad spectrum antibiotic activity, isolated from Saccharopolyspora erythraea (formerly Streptomyces erythreus) in 1952. Erythromycin is one of only a handful of microbial metabolites to have profoundly shaped the treatment of bacterial disease in the last 50 years. Erythromycin has given rise to new generations of semi-synthetic derivatives with improved stability and potency. Our product has been HPLC-purified to remove contaminants and degradation products.

定義

An antibiotic produced by growth of Streptomyces erythreus Waksman. It is effective against infections caused by Gram-positive bacteria, including some β-hemolytic streptococci, pneumococci, and staphylococci.

適応症

Erythromycin is an antibiotic in the macrolide family that also has promotility effects because it is a motilin agonist.

抗菌性

Gram-positive rods, including Clostridium spp. (MIC50 0.1–1 mg/L), C. diphtheriae (MIC50 0.1–1 mg/L), L. monocytogenes (MIC50 0.1–0.3 mg/L) and Bacillus anthracis (MIC50 0.5–1.0 mg/L), are generally susceptible. Most strains of M. scrofulaceum and M. kansasii are susceptible (MIC50 0.5–2 mg/L), but M. intracellulare is often and M. fortuitum regularly resistant. Nocardia isolates are resistant. H. ducreyi, B. pertussis (MIC50 0.03–0.25 mg/L), some Brucella, Flavobacterium, Legionella (MIC50 0.1–0.5 mg/L) and Pasteurella spp. are susceptible. H. pylori (MIC 0.06–0.25 mg/L) and C. jejuni are usually susceptible, but C. coli may be resistant. Most anaerobic bacteria, including Actinomyces and Arachnia spp., are susceptible or moderately so, but B. fragilis and Fusobacterium spp. are resistant. T. pallidum and Borrelia spp. are susceptible, as are Chlamydia spp. (MIC ≤0.25 mg/L), M. pneumoniae and Rickettsia spp. M. hominis and Ureaplasma spp. are resistant.
Enterobacteriaceae are usually resistant. Activity rises with increasing pH up to 8.5. Incubation in 5–6% CO2 raises the MIC for H. influenzae from 0.5–8 to 4–32 mg/L; MICs for Str. pneumoniae and Str. pyogenes also rise steeply. Activity is predominantly bacteristatic.

獲得抵抗性

In Europe, the USA and other countries the incidence of resistance in Str. pneumoniae ranges from 5% to over 60%. In Str. pneumoniae strains resistant or intermediately susceptible to penicillin G, resistance rates above 80% have been reported. Increasing rates of resistance in clinical isolates of Str. pyogenes have also been reported, threatening its use as an alternative to penicillin G in allergic patients.
Lower rates of resistance have been reported in other bacterial species, including methicillin-resistant Staph. aureus, coagulase-negative staphylococci, Str. agalactiae, Lancefield group C and G streptococci, viridans group streptococci, H. pylori, T. pallidum, C. diphtheriae and N. gonorrhoeae.

応用例（製薬）

A natural antibiotic produced as a complex of six components (A–F) by Saccharopolyspora erythraea. Only erythromycin A has been developed for clinical use. It is available in a large number of forms for oral administration: the base compound (enteric- or film-coated to prevent destruction by gastric acidity); 2′-propionate and 2′-ethylsuccinate esters; a stearate salt; estolate and acistrate salts of 2′-esters. The 2′-esters and their salts have improved pharmacokinetic and pharmaceutical properties and are less bitter than erythromycin. It is also formulated as the lactobionate and gluceptate forparenteral use.

生物活性

Erythromycin is the principal one in antimicrobial drugs. Although available as the parent entity, semisynthetic derivatives have proved to be clinically superior to the natural cogener. Like the tetracyclines, synthetic transformations in the macrolide series have not significantly altered their antibacterial spectra, but have improved the pharmacodynamic properties. For example, the propionate ester of erythromycin lauryl sulfate (erythromycin estolate) has shown greater acid stability than the unesterified parent substance. Although the estolate appears in the blood somewhat more slowly, the peak serum levels reached are higher and persist longer than other forms of the drug. However, cholestatic hepatitis may occasionally follow administration of the estolate and, for that reason, the stearate is often preferred. Erythromycin is effective against Group A and other nonenterococcal streptococci, Corynebacterium diphtheriae, Legionella pneumophila, Chlamydia trachomatis, Mycoplasma pneumoniae, and Flavobacterium. Because of the extensive use of erythromycin in hospitals, a number of Staph. aureus strains have become highly resistant to the drug. For this reason, erythromycin has been used in combination with chloramphenicol. This combination is also used in the treatment of severe sepsis when etiology is unknown and patient is allergic to penicillin.

作用機序

Macrolides are inhibitors of protein synthesis at the ribosomes. They impair the elongation cycle of the peptidyl chain by specifically binding to the 50S subunit of the ribosome. Specificity toward prokaryotes relies upon the absence of 50S ribosomes in eukaryotes. The main interaction site is located at the central loop of the domain V of the 23S rRNA, at the vicinity of the peptidyl transferase center. The macrolide binding site is located at the entrance of the exit tunnel used by the nascent peptide chain to escape from the ribosome, at the place where the central loop of domain V interacts with proteins L4 and L22 and with the loop of 754 Macrolides and Ketolides hairpin 35 in domain II of rRNA. Interaction occurs via the formation of hydrogen-bonds between the reactive groups (2u-OH) of the desosamine sugar and the lactone ring and adenine residue 2058. This explains why mutation or methylation in position 2058 as well as mutations in proteins L4 and L22 confer resistance to macrolides. The binding site of macrolides on the ribosome overlaps that of chloramphenicol or lincosamides such as clindamycin, explaining pharmacologic antagonism between these antibiotic classes as well as cross-resistance.

薬理学

Erythromycin inhibits bacterial protein synthesis by reversibly binding with their 50 S ribosomal subunit, thus blocking the formation of new peptide bonds. Erythromycin is classified as a bacteriostatic antibiotic.
However, it can also exhibit a bactericidal effect against a few types of microbes at certain concentrations.
Bacterial resistance to erythromycin can originate by two possible mechanisms: the inability of reaching the cell membrane, which is particularly relevant in the case of the microorganisms Enterobacteriaceae, or in the case of the presence of a methylated alanine in the 23 S ribosomal RNA of the 50 S subunit, which lowers the affinity of erythromycin to it. Erythromycin acts on Gram-positive (staphylococci both produced and not produced by penicillinase, streptococci, pneumococci, clostridia) and a few Gram-negative microorganisms (gonococci, brucelli, hemophile and whooping cough bacilli, legionelli), mycoplasma, chlamydia, spirochaeta, and Rickettsia. Colon and blue-pus bacilli, as well as the bacilli shigella, salmonella, and others are resistant to erythromycin.

臨床応用

Erythromycin is used (offlabel indication) to accelerate gastric emptying in diabetic gastroparesis and postoperative gastroparesis. Tachyphylaxis will occur, so it cannot be used uninterruptedly for long periods.

安全性プロファイル

Poison by intravenous and intramuscular routes. Moderately toxic by ingestion, intraperitoneal, and subcutaneous routes. An experimental teratogen. Other experimental reproductive effects. Mutation data reported. When heated to decomposition it emits toxic fumes of NOx.

純化方法

It recrystallises from H2O to form hydrated crystals which melt at ca 135-140o, resolidifies and melts again at 190-193o. The melting point after drying at 56o/8mm is that of the anhydrous material and is at 137-140o. Its solubility in H2O is ~2mg/mL. The hydrochloride has m 170o, 173o (from aqueous EtOH, EtOH/Et2O). [Flynn et al. J Am Chem Soc 76 3121 1954, constitution: Wiley et al. J Am Chem Soc 79 6062 1957]. [Beilstein 18/10 V 398.]