Bacterial cell wall synthesis
Bacterial cell wall peptidoglycan precursor (D-alanyl-D-alanine [D-Ala-D-Ala] terminal motif); [2]

In vitro activity: Vancomycin is a large glycopeptide compound with a molecular weight of 1450 Da. Vancomycin is a unique glycopeptide structurally unrelated to any currently available antibiotic. It also has a unique mode of action inhibiting the second stage of cell wall synthesis of susceptible bacteria. Vancomycin is active against a large number of species of Gram-positive bacteria, such as Staphylococcus aureus, Staph. epidermidis, Str. agalactiae, Str. bovis, Str. mutans, viridans streptococci, enterococci.

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Vancomycin HCl exhibited potent in vitro activity against Gram-positive bacteria, including Staphylococcus aureus (MIC range: 0.5-2 μg/mL), coagulase-negative staphylococci (MIC range: 0.25-1 μg/mL), Streptococcus pneumoniae (MIC range: 0.125-0.5 μg/mL), and Enterococcus faecalis (MIC range: 1-4 μg/mL) [2]
- It inhibited bacterial cell wall synthesis by binding to the D-Ala-D-Ala terminal of peptidoglycan precursors, preventing cross-linking of peptidoglycan strands and leading to bacterial cell lysis [2]
- No significant activity was observed against Gram-negative bacteria due to inability to penetrate the outer membrane [2]

Vancomycin is administered intravenously, with a standard infusion time of at least 1 h, to minimize infusion-related adverse effects. Subjects with normal creatinine clearance, vancomycin has an α-distribution phase of 30 min to 1 h and a β-elimination half-life of 6-12 h. The volume of distribution is 0.4–1 L/kg. The binding of vancomycin to protein ranges from 10% to 50%. Factors that affect the overall activity of vancomycin include its tissue distribution, inoculum size, and protein-binding effects. Vancomycin treatment of infected mice is associated with improved clinical, diarrhea, and histopathology scores and survival during treatment.

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In a mouse model of Clostridium difficile infection (CDI), intraperitoneal administration of Vancomycin HCl (10 mg/kg/day for 5 days) reduced acute CDI severity but was associated with delayed intestinal tissue injury (observed on day 10 post-infection) [3]
- Vancomycin HCl treatment (10 mg/kg/day, ip, 5 days) in CDI mice led to clostridial overgrowth in the colon, with a 3.2-fold increase in C. difficile colony-forming units (CFUs) compared to untreated controls at day 7 post-treatment [3]
- Recurrence of CDI was observed in 45% of Vancomycin HCl-treated mice within 14 days post-treatment, significantly higher than the recurrence rate in untreated mice (12%) [3]

Vancomycin is a unique glycopeptide structurally unrelated to any currently available antibiotic. It also has a unique mode of action inhibiting the second stage of cell wall synthesis of susceptible bacteria. There is also evidence that vancomycin alters the permeability of the cell membrane and selectively inhibits ribonucleic acid synthesis. Induction of bacterial L-phase variants from susceptible organisms with vancomycin is extremely difficult, and such variants are unstable. Stable L-phase variants induced by other agents are susceptible to vancomycin. Vancomycin is active against a large number of species of Gram-positive bacteria, such as Staphylococcus aureus (including methicillin-resistant strains), Staph. epidermidis (including multiple-resistant strains), Streptococcus pneumoniae (including multiple-resistant strains), Str. pyogenes, Str. agalactiae, Str. bovis, Str. mutans, viridans streptococci, enterococci, Clostridium species, diphtheroids, Listeria monocytogenes, Actinomyces species and Lactobacillus species. There has been no increase in resistance to vancomycin during the past three decades. Enhancement of antimicrobial activity has been demonstrated with the combination of vancomycin and an aminoglycoside against Staph. aureus, Str. bovis, enterococci and viridans streptococci. The combination of vancomycin and rifampicin are antagonistic to most strains of Staph. aureus, though indifference and occasionally synergism have been shown, but is synergistic against strains of Staph. epidermidis. It shows indifference against enterococci. Vancomycin and fusidic acid are indifferent against Staph. aureus [2].

C. difficile toxin assay. C. difficile toxins A and B were detected using a modified protocol for the Tech Lab Toxin A/B II ELISA kit. Each stool sample was weighed and the amount of diluent per sample was normalized to provide the same stool mass-to-diluent ratio for each sample. The diluent-sample mixtures were homogenized by grinding and vortexing, and 1:10, 1:100, and 1:1,000 serial dilutions were made of the sample. A total of 150 μl of the 1:1,000 dilution of each sample was added to a precoated well provided in the kit. A negative control consisted of 150 μl of diluent, and a positive control consisted of 135 μl of diluent plus 3 drops of the positive control toxin A-B mixture provided in the kit. One drop of conjugate was added to each well, and the plate was incubated at 37°C for 50 min. Each well was washed three times with 150 μl of a 1× dilution of the wash buffer provided in the kit. Two drops of substrate were added to each well. After 10 min, 1 drop of stop solution was added to each well. The plate was allowed to sit for 2 min before being read in an ELISA reader [3].

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MIC determination by broth dilution method: Bacterial strains were inoculated into Mueller-Hinton broth containing serial two-fold dilutions of Vancomycin HCl (0.0625-64 μg/mL). Cultures were incubated at 37°C for 18-24 hours, and the MIC was defined as the lowest concentration of Vancomycin HCl that inhibited visible bacterial growth [2]
- Bacterial cell wall synthesis inhibition assay: Radiolabeled peptidoglycan precursors were added to bacterial cultures treated with Vancomycin HCl (0.5-4 μg/mL). After incubation at 37°C for 2 hours, bacterial cells were lysed, and radiolabeled peptidoglycan was quantified by scintillation counting to assess synthesis inhibition [2]

50 mg/kg; i.v.
Mice Murine model of C. difficile infection and treatment.[3]
The infection model is a modification of the published protocol of Chen et al. This protocol has been approved by the Center for Comparative Medicine at University of Virginia. C57BL/6 mice, male, 8 weeks old, were used. From 6 to 4 days prior to infection, mice were given an antibiotic cocktail containing vancomycin (0.0045 mg/g), colistin (0.0042 mg/g), gentamicin (0.0035 mg/g), and metronidazole (0.0215 mg/g) in drinking water. One day prior to infection, clindamycin (32 mg/kg of body weight) was injected subcutaneously. The mice were divided into the following groups: control uninfected, control infected, infected and treated with vancomycin (20 mg/kg), and infected and treated with comparator drugs—nitazoxanide, fidaxomicin, and metronidazole (all drugs given at 20 mg/kg/day). Food and water were allowed ad libitum. Although each mouse or treatment group was housed in a separate cage, all mice were housed in the same pod of the vivarium. Infection was performed with VPI 10463 (ATCC) as an inoculum of 104 or 105 administered by oral gavage. This strain produces both C. difficile toxins A (TcdA) and B (TcdB). One day postinfection, treated mice were given either vancomycin or nitazoxanide at 20 mg/kg each by oral gavage daily for 5 days and monitored for either 1 or 2 weeks postinfection. One set of experiments was performed in which infected mice were treated with vancomycin (50 mg/kg) daily for 1, 2, 3, or 5 days and were observed for 21 days postinfection or with vancomycin (20 mg/kg) daily for either 5 or 10 days and monitoring for 15 days postinfection. In a separate experiment, mice given a preinfection antibiotic regimen described above were treated with either vancomycin, fidaxomicin, or metronidazole at 20 mg/kg/day for 5 days and infected another 5 days later. Except when indicated, all comparator drugs were administered using the same dosage (20 mg/kg/day for 5 days) to equally compare efficacies, outcomes, and effects on selected gut floras between treatment groups as previously described. From another study, a group of control mice was given vancomycin but was not infected. A clinical scoring system was developed on the basis of weight loss, diarrhea, activity level, and appearance of eyes and hair (each parameter scored from 0 to 3, where 0 is normal and 3 is the worst; maximum score of 20). Stool specimens were collected daily. Diarrhea was scored as follows: 1 for soft or color change (yellow), 2 for wet tail or mucoid, and 3 for liquid or no stool (ileus). Mice judged moribund by the clinical score (score of >14) at any day and all surviving mice at the end of the experiment were sacrificed, and intestinal tissues and cecal contents were collected as described below. A separate set of experiments was performed for harvesting cecal contents for clostridial bacterial and toxin burdens at days 3, 6, 9, and 12 to 13 postinfection to follow changes at different time points of the study.Histopathology. Upon euthanasia, cecal and colonic tissues were fixed in 10% zinc formalin overnight and then placed in 10% ethanol before being sent for paraffin embedding and hematoxylin and eosin (H&E) staining at the University of Virginia Histology Research Core.
Histopathologic scoring was performed coded (C.A.W. and M.S.R.). H&E-stained tissues were scored for mucosal disruption, mucosal hypertrophy, inflammation, vascular congestion and exudates, and submucosal edema (each parameter was graded from 0 to 3, with 0 as normal and 3 worst; maximum score of 15) as we previously described in detail.

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Mouse Clostridium difficile infection model: Female C57BL/6 mice (6-8 weeks old) were pretreated with a cocktail of antibiotics (oral gavage) for 5 days to disrupt gut microbiota. Two days after antibiotic withdrawal, mice were challenged with C. difficile spores (oral gavage). Vancomycin HCl was dissolved in sterile saline and administered via intraperitoneal injection at 10 mg/kg/day for 5 days, starting 24 hours post-challenge. Mice were euthanized at day 5 (end of treatment) or day 10 (post-treatment) for tissue collection and bacterial CFU counting [3]

The bioavailability of oral vancomycin hydrochloride in humans is less than 5% because it is poorly absorbed in the gastrointestinal tract [1]
- After intravenous administration (1 gram per 12 hours in adults), the peak plasma concentration (Cmax) of vancomycin hydrochloride is 25-40 μg/mL, and the terminal half-life (t1/2) is 6-10 hours [1]
- The volume of distribution (Vd) in adults is 0.4-1.0 L/kg, mainly distributed in the extracellular fluid [1]
- Vancomycin hydrochloride is not metabolized in the body; about 90-95% of vancomycin is excreted unchanged in the urine via glomerular filtration [1]
- The plasma protein binding rate of vancomycin hydrochloride is 10-50%, and the binding rate is even lower in patients with renal insufficiency [1]

In mice treated with vancomycin hydrochloride, intestinal epithelial damage was delayed, characterized by atrophy of colonic villi and increased inflammatory cell infiltration [3]. Nephrotoxicity (reversible tubular damage) has been reported in humans at high plasma concentrations (>80 μg/mL) [1].

[1]. The pharmacokinetic and pharmacodynamic properties of vancomycin. Clin Infect Dis. 2006 Jan 1;42 Suppl 1:S35-9.

[2]. Mode of action and in-vitro activity of vancomycin. J Antimicrob Chemother. 1984 Dec;14 Suppl D:7-18.

[3]. Vancomycin treatment's association with delayed intestinal tissue injury, clostridial overgrowth, and recurrence of Clostridium difficile infection in mice. Antimicrob Agents Chemother. 2013 Feb;57(2):689-96.

Vancomycin hydrochloride is a prescription antimicrobial drug approved by the U.S. Food and Drug Administration (FDA) for the treatment of certain bacterial infections, such as those caused by Clostridium difficile and Staphylococcus aureus. Clostridium difficile and Staphylococcus aureus are bacteria that can cause opportunistic infections (OIs) in HIV-infected individuals. Opportunistic infections are those that are more common or more severe in people with weakened immune systems (such as HIV-infected individuals) than in people with healthy immune systems. Vancomycin hydrochloride is the hydrochloride salt of vancomycin, a branched-chain tricyclic glycosylated peptide with bactericidal activity against most microorganisms and bacteriostatic activity against enterococci. Unlike penicillins and cephalosporins, vancomycin binds tightly to the D-alanyl-D-alanine moiety in the cell wall precursor, thereby interfering with bacterial cell wall synthesis. This leads to the activation of bacterial autolysins, which disrupt the cell wall through lysis. Vancomycin may also alter the permeability of the bacterial cytoplasmic membrane and may selectively inhibit RNA synthesis.
An antibacterial agent, extracted from Streptomyces orientalis. It is a glycopeptide antibiotic associated with listomomycin that inhibits bacterial cell wall assembly and is toxic to the kidneys and inner ear.
See also: Vancomycin (with active fraction).

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Vancomycin hydrochloride is a glycopeptide antibiotic primarily used to treat serious infections caused by methicillin-resistant Staphylococcus aureus (MRSA) and other multidrug-resistant Gram-positive bacteria[1][2] - Its mechanism of action is to bind to the D-Ala-D-Ala residues of bacterial peptidoglycan precursors, blocking transpeptidation and transglycosylation steps in cell wall synthesis, leading to bacterial death[2] - The association between vancomycin hydrochloride treatment and recurrent Clostridium difficile infection (CDI) may be related to its disruption of the gut microbiota and selective promotion of Clostridium difficile spore growth[3]

C66H75CL2N9O24.HCL

1485.71

1483.406

C, 53.36; H, 5.16; Cl, 7.16; N, 8.48; O, 25.84

1404-93-9

Vancomycin;1404-90-6; 1404-93-9 (HCl); 123409-00-7 (HCl hydrate)

6420023

White to off-white solid powder.

1.7±0.1 g/cm3

>190°C (dec.)

87℃

1.735

-1.44

20

26

13

102

2960

18

C[C@@H]1O[C@@]([H])(O[C@@H]2[C@@H](O)[C@H](O)[C@@H](CO)O[C@H]2OC3=C(OC4=C(Cl)C=C([C@@H](O)[C@](NC([C@]5([H])NC6=O)=O)(C(N[C@]([H])(C(O)=O)C7=CC(O)=CC(O)=C7C8=C(O)C=CC5=C8)=O)[H])C=C4)C=C([C@@]6([H])NC([C@H](CC(N)=O)NC9=O)=O)C=C3OC%10=CC=C([C@@H](O)[C@H]9NC([C@H](NC)C(C)(C)C)=O)C=C%10Cl)C[C@](C)(N)[C@@H]1O.[H]Cl

LCTORFDMHNKUSG-XTTLPDOESA-N

InChI=1S/C66H75Cl2N9O24.ClH/c1-23(2)12-34(71-5)58(88)76-49-51(83)26-7-10-38(32(67)14-26)97-40-16-28-17-41(55(40)101-65-56(54(86)53(85)42(22-78)99-65)100-44-21-66(4,70)57(87)24(3)96-44)98-39-11-8-27(15-33(39)68)52(84)50-63(93)75-48(64(94)95)31-18-29(79)19-37(81)45(31)30-13-25(6-9-36(30)80)46(60(90)77-50)74-61(91)47(28)73-59(89)35(20-43(69)82)72-62(49)92;/h6-11,13-19,23-24,34-35,42,44,46-54,56-57,65,71,78-81,83-87H,12,20-22,70H2,1-5H3,(H2,69,82)(H,72,92)(H,73,89)(H,74,91)(H,75,93)(H,76,88)(H,77,90)(H,94,95);1H/t24-,34+,35-,42+,44-,46+,47+,48-,49+,50-,51+,52+,53+,54-,56+,57+,65-,66-;/m0./s1

(1S,2R,18R,19R,22S,25R,28R,40S)- 48- {[(2S,3R,4S,5S,6R)- 3- {[(2S,4S,5S,6S)- 4- amino- 5- hydroxy- 4,6- dimethyloxan- 2- yl]oxy}- 4,5- dihydroxy- 6- (hydroxymethyl)oxan- 2- yl]oxy}- 22- (carbamoylmethyl)- 5,15- dichloro- 2,18,32,35,37- pentahydroxy- 19- [(2R)- 4- methyl- 2- (methylamino)pentanamido]- 20,23,26,42,44- pentaoxo- 7,13- dioxa- 21,24,27,41,43- pentaazaoctacyclo[26.14.2.23,6.214,17.18,12.129,33.010,25.034,39]pentaconta- 3,5,8(48),9,11,14,16,29(45),30,32,34,36,38,46,49- pentadecaene- 40- carboxylic acid hydrochloride

Vancomycin HCl; Vanco-saar; Vancocin; Vancocin HCl; Vancocine.

2934.99.9001

Powder      -20°C    3 years

                     4°C     2 years

In solvent   -80°C    6 months

                  -20°C    1 month

Note: Please store this product in a sealed and protected environment, avoid exposure to moisture.

Room temperature (This product is stable at ambient temperature for a few days during ordinary shipping and time spent in Customs)

H2O : ~33.33 mg/mL (~22.43 mM ) DMSO : ~24 mg/mL (~16.15 mM )

Solubility in Formulation 1: ≥ 2.08 mg/mL (1.40 mM) (saturation unknown) in 10% DMSO + 40% PEG300 + 5% Tween80 + 45% Saline (add these co-solvents sequentially from left to right, and one by one), clear solution.
For example, if 1 mL of working solution is to be prepared, you can add 100 μL of 20.8 mg/mL clear DMSO stock solution to 400 μL PEG300 and mix evenly; then add 50 μL Tween-80 to the above solution and mix evenly; then add 450 μL normal saline to adjust the volume to 1 mL.
Preparation of saline: Dissolve 0.9 g of sodium chloride in 100 mL ddH₂ O to obtain a clear solution.

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Solubility in Formulation 2: ≥ 2.08 mg/mL (1.40 mM) (saturation unknown) in 10% DMSO + 90% (20% SBE-β-CD in Saline) (add these co-solvents sequentially from left to right, and one by one), clear solution.
For example, if 1 mL of working solution is to be prepared, you can add 100 μL of 20.8 mg/mL clear DMSO stock solution to 900 μL of 20% SBE-β-CD physiological saline solution and mix evenly.
Preparation of 20% SBE-β-CD in Saline (4°C，1 week): Dissolve 2 g SBE-β-CD in 10 mL saline to obtain a clear solution.

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Solubility in Formulation 3: ≥ 2.08 mg/mL (1.40 mM) (saturation unknown) in 10% DMSO + 90% Corn Oil (add these co-solvents sequentially from left to right, and one by one), clear solution.
For example, if 1 mL of working solution is to be prepared, you can add 100 μL of 20.8 mg/mL clear DMSO stock solution to 900 μL of corn oil and mix evenly.

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Solubility in Formulation 4: 10% DMSO+40% PEG300+5% Tween-80+45% Saline: ≥ 2.08 mg/mL (1.40 mM)

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Solubility in Formulation 5: 130 mg/mL (87.50 mM) in PBS (add these co-solvents sequentially from left to right, and one by one), clear solution; with ultrasonication.

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 (Please use freshly prepared in vivo formulations for optimal results.)