c. difficile

Penicillin V Potassium (Phenoxymethylpenicillin potassium salt) 是一种有口服活性的抗生素。它可抑制链球菌，艰难梭菌和金黄色葡萄球菌的生长，可研究中耳炎，鼻窦炎，咽炎和扁桃体炎。

Ibezapolstat (ACX-362E) 是一种具有口服活性的 DNA 聚合酶 IIIC 抑制剂，是一种具有抗菌活性的抗生素，抑制艰难梭菌，可用于研究艰难梭菌感染 。

MGB-BP-3 是一种合成抗生素，具有杀菌活性，抑制细菌 DNA 复制，可用于研究复发性艰难梭菌感染。

Ridinilazole (SMT19969) 是一种新型的窄谱非吸收性抗生素。它显示出对艰难梭菌的有效抑制作用 (MIC90=0.125 mg L)，并且比甲硝唑 (MIC90 = 8 mg L) 或万古霉素 (MIC90 = 2 mg L) 更有效。

Cholic acid anilide is a synthetic bile acid and derivative of cholic acid that inhibits the germination of C. difficile strain R20291 spores in vitro (IC50 = 1.8 μM).1 |1. Sharma, S.K., Yip, C., Esposito, E.X., et al. The design, synthesis, and characterizations of spore germination inhibitors effective against an epidemic strain of Clostridium difficile. J. Med. Chem. 61(15), 6759-6778 (2018).

Isodeoxycholic Acid 是一种胆汁酸，由肠道细菌通过脱氧胆酸的表聚作用形成。Isodeoxycholic acid 的临界胶束浓度高于二氯苯甲醚，这表明它的去污活性降低了，而且在抑制七种肠道共生细菌生长方面的活性低于二氯苯甲醚。Isodeoxycholic Acid（0.1%）能抑制几种艰难梭菌菌株在牛磺胆酸诱导下的孢子萌发，并能降低艰难梭菌培养上清对 Vero 细胞的细胞毒性。在高脂饮食诱发肥胖的大鼠模型中，血浆中的Isodeoxycholic acid 水平比正常饮食的大鼠低。

Phenelfamycin E is an antibiotic originally isolated from Streptomyces. It is active against β-hemolytic Streptoccus, S. pneumoniae, C. difficile, C. perfringens, and P. magnus128 μg/ml). Phenelfamycin E (4-64 mg/kg) increases survival in a mouse model of lethal S. pyogenes infection in a dose-dependent manner. Dietary administration of phenelfamycin E increases body weight in chickens.

ATPase-IN-2 is a compound that acts as an inhibitor of ATPase, with an IC50 value of 0.9 μM. It also inhibits the glycohydrolase activity of C. difficile toxin B (TcdB) with an AC50 value of 30.91 μM. ATPase-IN-2 is commonly utilized in ATP-related research [1].

Cefminox (Sodium) is a new cephamycin antibiotic possessing a D-amino acid moiety derived from D-cysteine at the C-7B side chain. Cefminox is active against a wide range of bacteria, especially Gram-negative and anaerobic bacteria. Cefminox shows excellent in vivo efficacy (ED50) which is higher than would be expected from its in vitro activity (MIC). Moreover, cefminox possesses more potent activity in suppression of bacterial regrowth than other cephems[1]. Cefminox (Sodium) was the most active beta-lactam, with an MIC at which 50% of isolates are inhibited (MIC50) of 1.0 microg ml and an MIC90 of 16.0 microg ml. Cefminox was especially active against Bacteroides fragilis (MIC90, 2.0 microg ml), Bacteroides thetaiotaomicron (MIC90, 4.0 microg ml), fusobacteria (MIC90, 1.0 microg ml), peptostreptococci (MIC90, 2.0 microg ml), and clostridia, including Clostridium difficile (MIC90, 2.0 microg ml)[2]. The use of a single preoperative dose of cefminox was similar in efficacy to 3 doses of cefoxitin administered every 4 hours, and that the serum and tissue concentrations attained provide adequate antibiotic coverage[3]. Moreover, cefminox as a dual agonist of IP (Prostacyclin receptor) and PPARγ (peroxisome proliferator-activated receptor-gamma) that significantly inhibits PASMC proliferation by up-regulation of PTEN (phosphatase and tensin homolog) and cAMP ( cyclic adenosine monophosphate), suggesting that it has potential for treatment of PAH(pulmonary arterial hypertension)[4].

Benastatin B is a polyketide synthase-derived benastatin that has been found in Streptomyces and has diverse biological activities. It inhibits glutathione S-transferase (GST; Ki = 3.7 µM for the rat liver enzyme).2 Benastatin B also inhibits the transglycosylase activity of A. baumannii, C. difficile, E. coli, and S. aureus recombinant penicillin-binding proteins (PBPs; IC50s = 16, 53.3, 30.7, and 31.6 µM, respectively).3 It is active against several bacteria, including methicillin-resistant S. aureus (MRSA; MIC = 3.12 µg ml).

Bezlotoxumab 是一种针对 C. difficile 毒素 B 的人单克隆抗体。Bezlotoxumab 与 C. difficile 毒素 B 结合，可预防肠上皮损伤和结肠炎。

Actoxumab 是一种针对艰难梭菌毒素 A (C. difficile toxin A) 的人源化单克隆抗体，阻止 TcdA 与靶细胞的结合，通过抑制 TcdA 的第一步来中和毒素活性。

Antibacterialagent 156 (Compound 57) 是针对 C. difficile 的选择性高效杀菌化合物，作用机制为目标细胞壁合成。其对101株的MIMIC50值和MIC90值分别为0.5 μg mL与1 μg mL。

Antibacterialagent 159 (Compound 6d) 是一款高效抗菌化合物，具备针对脓疱疮和C. difficile感染（CDI）的抗菌活性。其使用过程中未发现C. difficile复发现象，并对益生肠道菌群仅有微弱影响。

Scandoside 是一种可从弥散嗜血杆菌中分离得到的环烯醚类化合物，具有抗炎活性，抑制诱导型一氧化氮合酶（iNOS）、环氧合酶-2（COX-2）、TNF-α和IL-6信使RNA（mRNA）的表达水平，抑制核转录因子kappa-B alpaha（IκB-α）、p38、细胞外信号调节激酶（ERK）和c-Jun N末端激酶（JNK）抑制剂的磷酸化。

D-CopA3 是 MDM2 的抑制剂并激活 p53 信号通路。在结直肠癌细胞系 HCT-116、LoVo 和 RKO 中，D-CopA3 显示出细胞毒性（IC50=15-18 μM），并诱导 JNK Beclin-1 介导的自噬 (autophagy)。此外，它下调细胞周期抑制蛋白 p21Cip1 Waf1 的表达，增强粘膜屏障功能，减少炎症介质的渗透。D-CopA3 在小鼠 C. difficile 毒素 A 诱发的急性肠炎模型和 DSS 诱发的慢性结肠炎模型中展现抗炎活性，且在小鼠 HCT-116 异种移植模型中具有抗肿瘤作用。