SOB Medium - BioReagent

Cat. No.: S1528469

QUALITÉ & PURETÉ BioReagent

Storage

Room temperature

Shipped In

Normal

Vue d’ensemble

For the cultivation of Escherichia coli strains for molecular genetics

Spécifications

Spécifications et pureté

BioReagent

Conditions de stockage de stockage

Room temperature

Expédié en

Normal

Grade

BioReagent

Product Line

Produits biologiques

Application Protocols

• Item-specific: Manufacturer protocols are not provided in the Product Data. Follow your laboratory SOPs and the label/CoA for this item.

• Example protocols (literature/general; adapt to your SOP and this item’s formulation):

  1. Preparation of base SOB medium

     • Weigh the specified grams of dehydrated SOB per liter of purified water (use the exact g/L from this item’s label).
     • Stir to dissolve; adjust pH toward ~7.0 if directed by the label.
     • Distribute to suitable vessels; autoclave (e.g., 121 °C, 15–20 min). Allow to cool to ~50–55 °C.
     • Aseptically add sterile-filtered Mg2+ supplements per your protocol to achieve literature-typical SOB cation levels. Mix and store or use promptly.

  2. Transformation recovery (chemically competent E. coli)

     • After heat shock, add pre-warmed SOB (no antibiotics) to the cells to a convenient volume (e.g., 0.9–1 mL total in a microcentrifuge tube).
     • Incubate at 37 °C with shaking (200–250 rpm) for 45–60 minutes.
     • Plate appropriate volumes on selective agar; incubate overnight.

  3. Electroporation recovery

     • Immediately add room-temp SOB after pulsing to restore ionic strength; incubate 1 hour at 37 °C with shaking before plating.

Note: Exact grams-per-liter, pH targets, and supplement amounts are not specified for this item; rely on the current CoA/Spec Sheet.

Biological Roles

• Item-specific (from Product Data): Research Use Only. No clinical/diagnostic use.

• Functional role in microbiology (literature/general):

  • SOB Medium provides amino nitrogen (peptides/amino acids), vitamins/cofactors, and controlled ionic strength supporting rapid growth and robust recovery of E. coli, especially post-transformation.
  • Divalent cations (Mg2+) improve membrane stability and can enhance transformation survival; K+ assists in maintaining intracellular ionic homeostasis.
  • Absence of glucose (versus SOC) can limit overflow metabolism (acetate formation) during short outgrowth windows, which is beneficial for certain competent strains.

• Component-level contributions (typical, literature):

  • Tryptone/peptone: Supplies peptides and amino acids for protein synthesis.
  • Yeast extract: Source of vitamins (e.g., B-complex), nucleotides, and trace elements that support rapid growth and recovery.
  • Salts (NaCl/KCl): Establish osmotic balance and influence membrane potential; important for electrotransformation compatibility.
  • MgCl2/MgSO4: Added aseptically after sterilization to avoid precipitation and degradation; support ribosome function and membrane processes.

• Use cases in workflows (literature):

  • Post-transformation outgrowth before selection.
  • Phage work (e.g., M13) where divalent cations and rich nutrients facilitate infection/propagation.

For this specific product, consult the CoA/Spec Sheet for any formulation nuances that could affect particular strains or applications.

Buffer Applications

SOB Medium is not a dedicated buffering system; it is a complex growth medium.

• Item-specific: No buffer specifications provided; refer to CoA/Spec Sheet.

• General notes (literature):

  • Working pH is typically adjusted near neutral (~7.0 at 25 °C) during preparation, but the medium lacks a strong buffering pair (e.g., phosphate, Tris) at defined molarity.
  • During bacterial growth, metabolic byproducts can acidify the medium; SOB is therefore unsuitable where tight pH control is required.
  • For experiments requiring controlled pH, use defined buffers (e.g., phosphate, MOPS, HEPES) or defined media incorporating buffering capacity.

• Practical tip:

  • If limited buffering is desired without altering SOB’s nutrient profile, investigators sometimes co-supplement with low-millimolar phosphate; however, such modifications should be validated for the target strain and application and are not part of standard SOB formulations (literature).

For precise buffer preparation (pH targets, ionic strengths), consult standard buffer tables rather than using SOB.

Green Alternatives

While green chemistry frameworks target chemical synthesis solvents and reagents, media selection can still impact sustainability and waste.

• Context (general): SOB Medium is an aqueous, peptide/yeast extract-based formulation. Environmental considerations center on sourcing, preparation energy, and biowaste handling rather than solvent hazards.

• Comparative considerations (literature/general):

  • Carbon and nitrogen sources: Plant-derived peptones and sustainably produced yeast extract can reduce environmental footprint compared with animal-derived digests.
  • Energy use: Autoclaving consumes energy; preparing consolidated batches and using validated sterilization cycles can reduce energy per liter.
  • Waste minimization: Accurate scaling to demand reduces unused sterile medium disposal; prompt inactivation of biological waste (autoclave, chemical disinfectants) improves biosafety and reduces downstream treatment burden.

• Alternative media tradeoffs (literature): | Medium | Nutrient richness | Typical use | Sustainability notes | |---|---|---|---| | LB | Lower | Routine cloning | Less material per liter but may require longer incubations | | SOB | Moderate–rich | Transformation recovery | No glucose; reduced risk of overflow metabolism | | SOC | SOB + glucose | Maximize recovery | Added carbon source increases COD in waste streams | | 2xYT/TB | Rich–very rich | High biomass | Higher raw material intensity; more nutrient-laden effluent |

• For this catalog item:

  • Specific sourcing (animal-free, certifications) and waste guidance: Not specified for this item; refer to CoA/Spec Sheet.

Adopt institutional green lab practices: energy-efficient sterilization, right-sizing batches, and proper biowaste management.

Pharmaceutical Uses

• Item-specific (from Product Data): Research Use Only. No clinical or therapeutic applications are claimed for this product.

• General/literature context:

  • Complex media like SOB are used in research and process development settings to culture laboratory E. coli strains for cloning, plasmid construction, and methodological development.
  • In regulated biomanufacturing, media selection is controlled by quality systems; media may need to meet pharmacopeial or vendor-specific QC attributes (bioburden, sterility, endotoxin). SOB itself is primarily a research medium and is not typically referenced in pharmacopeias.
  • For upstream development, SOB or SOC can be used during strain engineering phases before transfer to defined, scalable media suitable for GMP.

• For this catalog item:

  • Any certifications (USP/EP compliance), animal-origin status, endotoxin/bioburden specifications, or sterility claims: Not specified for this item; refer to CoA/Spec Sheet.

Users working under cGMP or GLP should confirm suitability, documentation, and change-control with the supplier and qualify media performance within their quality framework.

Physical Properties

• Item-specific (from Product Data):

  • Appearance: Not specified for this item; refer to CoA/Spec Sheet.
  • Molecular weight, molecular formula: Not applicable to complex media; not specified for this item.

• General/literature properties for SOB-type media (not specifications for this item):

  • Physical state: Typically supplied as a free-flowing beige to light tan powder (dehydrated medium) or as a ready-to-use sterile solution.
  • Solubility: Freely soluble in water; insoluble in organic solvents.
  • Typical working concentration: The dehydrated powder is reconstituted to a defined grams-per-liter dose per the supplier’s formulation (consult this item’s label/CoA for exact g/L).
  • pH (at working strength): Often adjusted to ~7.0 (at 25 °C) before sterilization (literature). Final pH depends on formulation and water quality.
  • Osmolality/ionic strength: Governed by salt content (e.g., NaCl/KCl) and divalent cations (Mg2+ added after sterilization). Values vary by vendor.
  • Thermal behavior: Dehydrated powder is stable at ambient conditions when dry; prepared solutions are heat-sensitive with respect to vitamin degradation. Autoclaving is used for base medium; certain additives (e.g., Mg2+, glucose for SOC) are filter-sterilized and added aseptically post-autoclave (literature practice).

• Refractive index, density, logP, pKa, boiling/melting point: Not applicable for a complex aqueous medium; not specified for this item.

Always verify exact preparation parameters (g/L, pH target) on the current CoA/Spec Sheet for this catalog number.

Quality and Grades

• Item-specific (from Product Data):

  • Grade/Purity: BioReagent

• What BioReagent grade typically implies (general explanation):

  • Intended for laboratory research use where consistent performance in biological assays and culture work is expected.
  • Emphasis on lot-to-lot consistency, contaminant control relevant to biology (e.g., low heavy metals, inhibitory residues), and microbiological quality.
  • Not certified for clinical, therapeutic, or GMP manufacturing unless explicitly stated.

• Performance considerations for SOB-type media (literature/general):

  • Growth performance is sensitive to raw material quality (e.g., peptide profile of tryptone, yeast extract vitamin content) and ionic composition (K+, Na+, Mg2+). BioReagent grade typically ensures reproducible E. coli growth rates and transformation recovery.
  • Divalent cations (Mg2+) and K+ are critical for competent cell recovery; their source purity (chloride vs sulfate) and addition method (post-sterilization) influence outcomes.

• What is specific vs. unspecified for this catalog item:

  • Formulation details, component sources, endotoxin/bioburden limits, and performance criteria: Not specified for this item; refer to CoA/Spec Sheet.
  • Stabilizers, antibiotics, or supplements: Not specified for this item; refer to CoA/Spec Sheet.

For regulated applications, request a CoA/Spec Sheet and any available QA statements (e.g., sterility, bioburden) for the exact lot.

Reaction and Applications

As a culture medium, SOB Medium is not used as a chemical reagent but has important laboratory applications in microbiology and molecular biology.

• Item-specific (from Product Data): Research Use Only.

• Core applications (literature/general):

  • Recovery of chemically and electroporated competent E. coli following transformation, where elevated Mg2+ and optimal ionic conditions enhance membrane repair and DNA uptake survival.
  • High-efficiency growth for early outgrowth after transformation prior to plating or selection, often providing improved colony yields versus LB.
  • Propagation of E. coli strains carrying plasmids, M13 phage-related work, and steps in cloning workflows where gentle, nutrient-rich recovery is advantageous.

• Practical tips (literature):

  • Temperature: Grow E. coli at 30–37 °C with aeration. For electroporation recovery, pre-warm SOB to room temp or 37 °C to reduce cold shock.
  • Aeration: Use baffled flasks with ≤20–25% fill volume or vigorous shaking (200–300 rpm) to maintain oxygenation.
  • Cations: Add sterile Mg2+ solutions after autoclaving; final Mg2+ concentrations on the order of 10 mM each from MgCl2 and MgSO4 are common in SOB protocols (verify against your SOP).
  • Transition to selection: After 45–60 minutes of outgrowth (no antibiotic), plate on selective agar to minimize satellite colonies and optimize expression of antibiotic resistance.

• Noteworthy distinctions:

  • SOB lacks glucose; SOC is SOB plus glucose, often preferred for chemical transformation recovery due to added carbon source. Choice depends on strain and transformation method.

Always follow institutional SOPs and the specific formulation instructions for this catalog item.

Reaction Conditions

This section normally details chemical reaction parameters (solvent, catalysts, yields). For SOB Medium, the analogous considerations are culture conditions rather than chemical reactions.

• Item-specific: No culture-condition specifications provided; refer to CoA/Spec Sheet.

• General culture conditions for E. coli using SOB (literature):

  • Temperature: 30–37 °C depending on strain and plasmid stability.
  • Aeration: Shaking at 200–300 rpm in baffled flasks with ≤20–25% fill volume. For microplates, use high-aeration lids and orbital shaking ≥800 rpm with small diameters.
  • Inoculation: For transformation recovery, add pre-warmed SOB immediately after heat shock or electroporation and incubate 45–60 min before plating on selective agar.
  • Antibiotics: Withhold selection during initial outgrowth to allow expression of resistance markers; add selection upon plating or after recovery if liquid selection is required.
  • Cations: Add sterile-filtered Mg2+ solutions post-autoclave to achieve literature-typical SOB cation levels; exact concentrations depend on your SOP.
  • pH: Start near neutral; monitor if extended cultivation is planned (SOB is weakly buffered).

• Expected outcomes (literature):

  • Compared with LB, SOB/SOC often improves transformation colony counts and early growth rates; magnitudes are strain- and protocol-dependent.

Consult your transformation protocol and this item’s label for any specific preparation or use notes.

Safety and Handling

• Item-specific (from Product Data):

  • Storage Conditions: Room temperature
  • Shipped In: Normal
  • GHS Classification / Signal Word / H-Statements / Pictograms: Not specified for this item; refer to SDS.

• General safety guidance for dehydrated microbiological media (literature/best practice):

  • PPE: Lab coat, safety glasses, and appropriate gloves to avoid skin/eye contact and inhalation of dust.
  • Dust control: Avoid creating dust clouds; use a balance enclosure or fume hood during weighing to minimize inhalation.
  • Hygiene: Wash hands thoroughly after handling. Do not eat, drink, or smoke in work area.
  • Incompatibilities: Strong oxidizers and strong acids/bases may degrade organic components.
  • Sterilization: Base medium is commonly autoclaved. Heat-labile supplements (e.g., Mg2+ solutions prepared in water, glucose for SOC) are filter-sterilized (0.22 µm) and added aseptically after cooling to ~50–55 °C (literature practice). Avoid overheating to limit Maillard reactions and vitamin loss.
  • Microbiological risk: Once prepared and inoculated, cultures may contain high titers of microorganisms. Handle according to institutional biosafety procedures; disinfect spills with appropriate biocides (e.g., 10% bleach), and autoclave waste prior to disposal.
  • First aid (overview): If on skin/eyes, rinse with water. If inhaled (powder), move to fresh air. If ingested, rinse mouth with water. Seek medical attention if irritation persists. Defer to SDS for authoritative instructions.

Always consult the product-specific SDS for definitive hazard, first-aid, and disposal guidance.

Solvent Selection

This product is a microbiological medium reconstituted in water; organic solvent selection is not applicable in the conventional synthetic-chemistry sense.

• Item-specific (from Product Data): None beyond room-temperature storage.

• Practical guidance (literature/general):

  • Primary solvent: Purified water (e.g., ASTM Type 1 or sterile water for injection-grade water for sensitive applications). Water quality impacts pH and clarity.
  • Reconstitution: Dissolve the specified grams per liter in water with stirring; adjust pH if directed by the label; bring to final volume. Autoclave the base medium if required.
  • Additives: Heat-labile solutions (e.g., Mg2+ salts for SOB; glucose when preparing SOC) should be prepared in water, sterilized by filtration (0.22 µm), and added aseptically to cooled medium (~50–55 °C).
  • Miscibility: Aqueous medium; incompatible with most organic solvents. Do not attempt to dissolve in alcohols or aprotic solvents.
  • Conductivity/osmolarity: Determined by salt content; use consistent water and follow label directions for reproducibility.

• Comparison to related media (literature):

  • LB: Lower nutrient density; often adequate for routine cloning.
  • 2xYT/TB: Higher peptide and yeast extract loads; can increase biomass but may alter plasmid copy number profiles.

Refer to the product’s CoA/Spec Sheet for the exact grams-per-liter and any pH targets required for this SKU.

Storage and Reconstitution

• Item-specific (from Product Data):

  • Storage Conditions: Room temperature
  • Shipped In: Normal

• Stability notes (general/literature):

  • Dehydrated medium: Store tightly closed in a cool, dry place at room temperature. Protect from moisture and contaminants. Avoid repeated opening in humid environments; consider desiccant.
  • Prepared liquid medium: For non-sterile solutions, use promptly. For sterile solutions, store at 2–8 °C and use within a few weeks; avoid prolonged storage due to nutrient/vitamin degradation. Do not freeze unless validated.

• Reconstitution (follow this item’s label/CoA for exact values):

  • Dissolve the specified grams of SOB Medium powder per liter of purified water with stirring.
  • Adjust pH if directed (literature often targets ~7.0 at 25 °C); bring to volume.
  • Autoclave the base medium as instructed. Cool to ~50–55 °C.
  • Aseptically add sterile-filtered Mg2+ supplements per your SOP to achieve literature-typical SOB cation levels. If preparing SOC, add sterile-filtered glucose per protocol.
  • Mix thoroughly and, if desired, dispense into sterile containers. Label with preparation date and components.

• Shelf life and specs specific to this SKU (e.g., acceptable pH range, sterility, bioburden): Not specified for this item; refer to CoA/Spec Sheet and SDS.

Research Use Only: Not for human or animal therapeutic use.

Structure and Identity

Brief description: SOB Medium (Super Optimal Broth) is a complex, undefined microbiological growth medium commonly used for Escherichia coli growth and recovery of competent cells.

• Item-specific (from Product Data):

  • SKU: S1528469
  • Product Name: SOB Medium
  • Grade/Purity: BioReagent
  • Single-compound identifiers (CAS, CID, InChIKey, SMILES, molecular formula, molecular weight): Not specified for this item; refer to CoA/Spec Sheet.

• Nature of material (general knowledge):

  • Type: Complex, peptide/yeast extract-based nutrient medium (mixture), not a single defined chemical entity.
  • Components (typical, literature; exact composition/amounts are manufacturer-dependent): peptone/tryptone (amino nitrogen source), yeast extract (vitamins, nucleotides), inorganic salts (e.g., NaCl, KCl), and divalent cations (Mg2+ added post-sterilization). Glucose is not included in SOB (present in SOC).

• Structural features (how to think about it):

  • Being a mixture, SOB has no discrete 2D/3D molecular structure. Functionally, it supplies amino acids/peptides, vitamins/cofactors, and controlled ionic strength/osmolarity conducive to rapid E. coli growth and transformation recovery.

• Related media (literature):

  • SOC = SOB + glucose (typically ~20 mM)
  • LB (Luria–Bertani): lower nutrient density than SOB
  • 2xYT/TB: richer alternatives with different salt/carbon profiles.

Note: For this specific catalog item, rely on the product label/CoA for exact formulation and any proprietary variations.

Synthetic Utility

This section pertains to roles as a chemical reagent or building block in organic/inorganic synthesis. SOB Medium is a biological growth medium and is not typically used in chemical synthesis.

• Applicability: Not applicable for this product type.

• Guidance:

  • For synthetic chemistry, refer to solvent and reagent sections of the catalog. If your workflow involves biocatalysis or whole-cell synthesis, SOB may support biomass generation, but the medium itself is not a reagent in the chemical transformation.
  • Consider defined buffers or specific salts if your aim is to control ionic strength or pH in chemoenzymatic reactions.

See Reaction & Applications for microbiology-focused uses relevant to SOB.

Target Specificity

Target specificity (antigens, epitopes, clone/isotype) is relevant to antibodies and affinity reagents, not to culture media.

• Item-specific: No target specificity information is provided or applicable for this product.

For organism applicability, SOB is broadly suitable for laboratory E. coli strains (literature). Strain-specific needs (e.g., auxotrophies) may require supplementation.