Biological buffer

Study of coxsackievirus B3 strain 28 (CVB3/28) stability using MOPS to improve buffering in the experimental medium revealed that MOPS (3-morpholinopropane-1-sulfonic acid) increased CVB3 stability and the effect was concentration dependent. Over the pH range 7.0-7.5, virus stability was affected by both pH and MOPS concentration. Computer-simulated molecular docking showed that MOPS can occupy the hydrophobic pocket in capsid protein VP1 where the sulfonic acid head group can form ionic and hydrogen bonds with Arg95 and Asn211 near the pocket opening. The effects of MOPS and hydrogen ion concentrations on the rate of virus decay were modeled by including corresponding parameters in a recent kinetic model. These results indicate that MOPS can directly associate with CVB3 and stabilize the virus, possibly by altering capsid conformational dynamics.[1]

The enzymatic degradation of polyethylene terephthalate (PET) occurs at mild reaction conditions and may find applications in environmentally friendly plastic waste recycling processes. The hydrolytic activity of the homologous polyester hydrolases LC cutinase (LCC) from a compost metagenome and TfCut2 from Thermobifida fusca KW3 against PET films was strongly influenced by the reaction medium buffers tris(hydroxymethyl)aminomethane (Tris), 3-(N-morpholino)propanesulfonic acid (MOPS), and sodium phosphate. LCC showed the highest initial hydrolysis rate of PET films in 0.2 m Tris, while the rate of TfCut2 was 2.1-fold lower at this buffer concentration. At a Tris concentration of 1 m, the hydrolysis rate of LCC decreased by more than 90% and of TfCut2 by about 80%. In 0.2 m MOPS or sodium phosphate buffer, no significant differences in the maximum initial hydrolysis rates of PET films by both enzymes were detected. When the concentration of MOPS was increased to 1 m, the hydrolysis rate of LCC decreased by about 90%. The activity of TfCut2 remained low compared to the increasing hydrolysis rates observed at higher concentrations of sodium phosphate buffer. In contrast, the activity of LCC did not change at different concentrations of this buffer. An inhibition study suggested a competitive inhibition of TfCut2 and LCC by Tris and MOPS. Molecular docking showed that Tris and MOPS interfered with the binding of the polymeric substrate in a groove located at the protein surface. A comparison of the K i values and the average binding energies indicated MOPS as the stronger inhibitor of the both enzymes.[2]

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Hydrolysis of PET films by LCC and TfCut2[2]
Polyethylene terephthalate films of 9 cm2 (about 150 mg) were added to reaction vials containing 0.1–2.8 μg·cm−2 of purified LCC or TfCut2 and 0.1–1 m Tris, sodium phosphate or MOPS buffer (pH 8.0) in a total volume of 1.8 mL. The pH of the buffers was adjusted at 60 °C using HCl for Tris and NaOH for MOPS buffer. The reaction vials were incubated at 60 °C on a thermo shaker (1000 rpm) for 1 h. Released hydrolysis products were quantified by RP‐HPLC 39. The sum of the released soluble products—TPA, mono‐(2‐hydroxyethyl) terephthalate (MHET), and bis‐(2‐hydroxyethyl) terephthalate (BHET) was used to determine the initial hydrolysis rate. All initial rates were determined at least in triplicate.[2]

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Inhibition of LCC and TfCut2 by Tris and MOPS[2]
Polyethylene terephthalate films of 1–9 cm2 (about 20–150 mg) were added to reaction vials containing purified LCC (1 μg) or TfCut2 (5 μg) and 0.2 m sodium phosphate buffer (pH 8.0) in a total volume of 1.8 mL. Tris (0.2–0.4 m, pH 8.0) and MOPS (0.05–0.3 m, pH 8.0) were added to the reaction mixture. The vials were incubated at 60 °C on a thermo shaker (1000 rpm) for 1 h. Released hydrolysis products were quantified by RP‐HPLC[2].

RDt3 cells (RD cells expressing truncated CAR (Cunningham et al., 2003)) and lab strain HeLa cells (Carson and Pirruccello, 2013) were maintained in Dulbecco’s modified Eagle’s medium with 10% fetal bovine serum in a 37°C incubator with 6% CO2. Five milliliters of 200 nM glutamine, 10 mL penicillin/streptomycin (10000 U/mL and 10 mg/mL, respectively) and 1.5 mL gentamicin (50 mg/mL) were added to each 1.1 liter of DMEM-10% serum (the complete medium is referred to as DMEM-10). MOPS was added to the DMEM-10 to the final experimental concentration, and pH was adjusted to target values using 4M NaOH. NaCl was added (50–200nM) to separate samples of DMEM-10 used as controls for salt effects. Separate 4mL aliquots of medium were placed in the incubator and used to determine the incubation pH at the end of each decay time course. Except at pH 7.4 (the pH of DMEM-10 in 6% CO2) the experimental pH was different than the initial adjusted pH of the DMEM-10 with MOPS.[1]

Quail LD50 oral >316 mg/kg

[1]. MOPS and coxsackievirus B3 stability. Virology. 2017 Jan 15;501:183-187.

[2]. Effect of Tris, MOPS, and phosphate buffers on the hydrolysis of polyethylene terephthalate films by polyester hydrolases. FEBS Open Bio. 2016 Jul 20;6(9):919-27.

[3]. Effect of Tris, MOPS, and phosphate buffers on the hydrolysis of polyethylene terephthalate films by polyester hydrolases. FEBS Open Bio. 2016 Jul 20;6(9):919-27.

3-(N-morpholino)propanesulfonic acid is a Good's buffer substance, pKa = 7.2 at 20 ℃. It is a member of morpholines, a MOPS and an organosulfonic acid. It is a conjugate acid of a 3-(N-morpholino)propanesulfonate. It is a tautomer of a 3-(N-morpholiniumyl)propanesulfonate.
3[N-Morpholino]propane sulfonic acid has been reported in Citrus reticulata and Citrus deliciosa with data available.
See also: 3-(N-morpholino)propanesulfonate (annotation moved to).

C7H15NO4S

209.26

209.072

1132-61-2

MOPS-d15;1219799-30-0; 71119-22-7 (sodium salt); 1132-61-2 (free acid)

70807

White to off-white solid powder

1.298 g/cm3

277-282 °C

116 °C

1.512

-1.91

1

5

4

13

227

0

DVLFYONBTKHTER-UHFFFAOYSA-N

InChI=1S/C7H15NO4S/c9-13(10,11)7-1-2-8-3-5-12-6-4-8/h1-7H2,(H,9,10,11)

3-morpholin-4-ylpropane-1-sulfonic acid

4-Morpholinepropanesulfonic acid; 3-Morpholinopropanesulfonic acid; 3-(N-Morpholino)propanesulfonic acid; 3-Morpholinopropane-1-sulfonic acid; 3[N-MORPHOLINO]PROPANE SULFONIC ACID; Morpholinopropane sulfonic acid;

2934.99.9001

Powder      -20°C    3 years

                     4°C     2 years

In solvent   -80°C    6 months

                  -20°C    1 month

Note: This product requires protection from light (avoid light exposure) during transportation and storage.

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

H2O: 50 mg/mL (238.94 mM)

Solubility in Formulation 1: ≥ 100 mg/mL (477.87 mM) (saturation unknown) in PBS (add these co-solvents sequentially from left to right, and one by one), clear solution.

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