Recombinant Bacillus licheniformis UPF0295 protein BLi00901/BL05075 (BLi00901, BL05075)

What is Bacillus licheniformis UPF0295 protein BLi00901/BL05075?

The UPF0295 protein BLi00901/BL05075 is a full-length protein comprising 115 amino acids derived from Bacillus licheniformis. The protein has the UniProt ID Q65M79 and belongs to the UPF0295 protein family. In recombinant form, it is typically expressed with an N-terminal His-tag to facilitate purification and detection . This protein is part of the extensive research being conducted on B. licheniformis, which is classified as a non-pathogenic, Risk Group 1 organism according to NIH guidelines and is widely distributed in nature .

What expression systems are commonly used for producing recombinant BLi00901/BL05075?

The primary expression system documented for BLi00901/BL05075 production is Escherichia coli. The recombinant protein is typically expressed with an N-terminal His-tag to facilitate purification . When designing expression systems for B. licheniformis proteins in general, researchers have used several approaches:

• Homologous expression: Using B. licheniformis itself as an expression host, such as B. licheniformis BL10, which has good protein expression capacity .

• Heterologous expression: E. coli remains the most common heterologous expression system due to its well-established genetic tools and rapid growth .

• Plasmid-based expression: Vectors such as pHY300PLK have been used to construct heterologous gene expression vectors in B. licheniformis .

What are the optimal storage conditions for recombinant BLi00901/BL05075?

The optimal storage conditions for recombinant BLi00901/BL05075 are:

• Long-term storage: Store at -20°C/-80°C, with aliquoting recommended for multiple use.

• Short-term storage: Working aliquots can be stored at 4°C for up to one week.

• Buffer composition: Tris/PBS-based buffer with 6% Trehalose at pH 8.0 is recommended for storage.

• Reconstitution protocol: Reconstitute the lyophilized protein in deionized sterile water to a concentration of 0.1-1.0 mg/mL.

• Cryoprotectant: Addition of 5-50% glycerol (final concentration) is recommended before aliquoting for long-term storage.

Important note: Repeated freezing and thawing is not recommended as it may lead to protein denaturation and loss of activity .

What are recommended protocols for purification of recombinant BLi00901/BL05075?

While specific purification protocols for BLi00901/BL05075 are not explicitly detailed in the search results, the following methodology can be inferred based on the His-tagged nature of the recombinant protein :

• Affinity Chromatography (Primary Purification):

  • Use Ni-NTA or IMAC (Immobilized Metal Affinity Chromatography) columns for capture of His-tagged BLi00901/BL05075.

  • Equilibrate column with binding buffer (typically 20-50 mM Tris-HCl, pH 8.0, 300 mM NaCl, 10 mM imidazole).

  • Apply cleared cell lysate to the column.

  • Wash with binding buffer containing 20-40 mM imidazole to remove non-specifically bound proteins.

  • Elute purified protein with elution buffer containing 250-500 mM imidazole.

• Secondary Purification (if higher purity is required):

  • Size exclusion chromatography (SEC) to separate the target protein from aggregates and other contaminants.

  • Ion exchange chromatography may be employed based on the theoretical isoelectric point of the protein.

• Quality Control:

  • SDS-PAGE analysis to confirm purity (>90% purity is typically achievable) .

  • Western blot using anti-His antibodies to confirm identity.

  • Mass spectrometry to verify molecular weight and integrity.

How can I optimize expression conditions for BLi00901/BL05075 in E. coli?

Based on general principles for optimizing recombinant protein expression and insights from the optimization of other B. licheniformis proteins , consider the following approach:

• Strain Selection:

  • Test multiple E. coli strains (BL21(DE3), Rosetta, Origami) to identify the optimal host.

  • Consider strains with enhanced disulfide bond formation capabilities if the native conformation requires disulfide bonds.

• Induction Parameters:

  • Optimize IPTG concentration (typically 0.1-1.0 mM range).

  • Test induction at different growth phases (mid-log phase is typically optimal).

  • Evaluate various induction temperatures (lower temperatures of 16-25°C often enhance soluble protein production).

• Medium Composition:

  • Apply experimental design methodologies similar to those used for other B. licheniformis proteins:

    • Single-factor experiments to identify significant variables.

    • Plackett‒Burman design to screen for significant factors affecting expression.

    • Central composite design (CCD) to optimize the identified significant factors .

• Expression Monitoring:

  • Use SDS-PAGE analysis at different time points to determine optimal harvest time.

  • Consider using Western blot analysis for more sensitive detection during optimization.

What analytical methods are most effective for characterizing BLi00901/BL05075?

For comprehensive characterization of recombinant BLi00901/BL05075, the following analytical methods are recommended:

• Structural Analysis:

  • SDS-PAGE for purity assessment and approximate molecular weight determination .

  • Mass spectrometry (MS) for accurate molecular weight and post-translational modification analysis.

  • Circular dichroism (CD) spectroscopy for secondary structure analysis.

  • Nuclear magnetic resonance (NMR) or X-ray crystallography for detailed 3D structural information.

• Functional Analysis:

  • While the specific function of UPF0295 is not well-characterized, potential membrane association suggests analysis of:

    • Membrane binding assays

    • Lipid interaction studies

    • Metal binding assays (given the presence of potential metal-binding motifs)

• Interaction Studies:

  • Pull-down assays using the His-tag to identify potential protein binding partners.

  • Surface Plasmon Resonance (SPR) for quantitative binding analysis.

  • Isothermal Titration Calorimetry (ITC) for thermodynamic analysis of binding interactions.

• Biophysical Characterization:

  • Dynamic Light Scattering (DLS) for assessing homogeneity and oligomeric state.

  • Differential Scanning Calorimetry (DSC) for thermal stability analysis.

  • Microscale Thermophoresis (MST) for studying interactions with other biomolecules.

How can I validate the functional activity of recombinant BLi00901/BL05075?

Since the specific function of UPF0295 protein BLi00901/BL05075 is not explicitly described in the search results, functional validation requires a systematic approach:

• Comparative Analysis:

  • Perform sequence homology and structural comparisons with functionally characterized homologs.

  • Use bioinformatics tools to predict potential functional domains and activities.

• Gene Knockout/Complementation Studies:

  • Generate a BLi00901/BL05075 knockout strain in B. licheniformis.

  • Assess phenotypic changes in the knockout strain.

  • Perform complementation with the recombinant protein to confirm specificity of observed phenotypes.

• Localization Studies:

  • Determine cellular localization using immunofluorescence microscopy or subcellular fractionation.

  • The amino acid sequence suggests possible membrane association, which can be validated using membrane fractionation techniques .

• Biochemical Assays:

  • Based on predicted function, develop assays for potential enzymatic activities.

  • Test for metal ion binding capacity using isothermal titration calorimetry.

  • Assess interaction with membrane components through lipid binding assays.

What is known about the biological function of UPF0295 protein BLi00901/BL05075?

• Potential Membrane Association:

  • The amino acid sequence contains multiple hydrophobic regions, suggesting possible membrane localization or interaction .

  • The presence of transmembrane-like segments indicates a potential role in membrane biology or transport.

• Metal Binding Potential:

  • The sequence contains cysteine-rich motifs (CPNC and CMHC) that could be involved in metal coordination or redox activity .

  • These motifs may suggest a role in metal homeostasis, redox sensing, or electron transfer.

• Contextual Function:

  • The protein may be part of B. licheniformis' adaptability to various environmental conditions, given that this bacterium is known for its metabolic versatility .

  • It could potentially be involved in stress response or adaptation to specific environmental conditions.

Further research is needed to elucidate the precise biological function, potentially through approaches such as gene knockout studies, interactome analysis, or comparative genomics with other bacterial species.

How does BLi00901/BL05075 compare to homologous proteins in other bacterial species?

While the search results don't provide direct comparative information about BLi00901/BL05075 homologs, a methodological approach for conducting such comparison would include:

• Sequence Alignment Analysis:

  • Perform BLAST searches to identify homologs in other bacterial species.

  • Use multiple sequence alignment tools (CLUSTALW, MUSCLE) to identify conserved regions.

  • Generate phylogenetic trees to understand evolutionary relationships between homologs.

• Structural Comparison:

  • Use protein structure prediction tools (AlphaFold, I-TASSER) to model BLi00901/BL05075 and its homologs.

  • Compare predicted structures to identify conserved structural features.

  • Analyze conservation of potential functional sites.

• Genomic Context Analysis:

  • Examine the genomic neighborhood of BLi00901/BL05075 in B. licheniformis and its homologs in other species.

  • Identify conserved gene clusters that might suggest functional associations.

  • Apply synteny analysis to infer potential operonic structures and co-regulated genes.

• Functional Conservation Assessment:

  • Compare experimental data on the function of homologs, if available.

  • Assess whether UPF0295 proteins show similar expression patterns across species.

  • Determine if knockout phenotypes are consistent across different bacterial species.

What experimental approaches are suitable for investigating protein-protein interactions involving BLi00901/BL05075?

Several complementary approaches can be employed to investigate protein-protein interactions of BLi00901/BL05075:

• Affinity-Based Methods:

  • His-tag pull-down assays utilizing the recombinant His-tagged BLi00901/BL05075 .

  • Co-immunoprecipitation (Co-IP) using antibodies against BLi00901/BL05075 or potential interaction partners.

  • Tandem affinity purification (TAP) for identifying stable protein complexes.

• Biophysical Interaction Analysis:

  • Surface Plasmon Resonance (SPR) for real-time binding kinetics.

  • Isothermal Titration Calorimetry (ITC) for thermodynamic analysis of binding interactions.

  • Microscale Thermophoresis (MST) for detecting interactions with minimal protein consumption.

• Crosslinking and Mass Spectrometry:

  • Chemical crosslinking of protein complexes followed by mass spectrometry analysis.

  • Hydrogen-deuterium exchange mass spectrometry (HDX-MS) to map interaction interfaces.

  • Protein interaction reporter (PIR) technology for capturing transient interactions.

• In vivo Approaches:

  • Bacterial two-hybrid system adapted for B. licheniformis proteins.

  • Fluorescence resonance energy transfer (FRET) using fluorescently tagged proteins.

  • Bimolecular fluorescence complementation (BiFC) for visualizing interactions in vivo.

• High-Throughput Screening:

  • Protein microarray analysis to identify potential interaction partners.

  • Yeast two-hybrid screening using a B. licheniformis genomic library.

  • Proximity-dependent biotin identification (BioID) to map protein neighborhoods.

How can CRISPR-Cas9 be used to study the function of BLi00901/BL05075 in B. licheniformis?

CRISPR-Cas9 technology provides powerful tools for functional genomics studies of BLi00901/BL05075:

• Gene Knockout Studies:

  • Design sgRNAs targeting the BLi00901 gene in B. licheniformis.

  • Generate knockout strains using CRISPR-Cas9 plasmid systems adapted for B. licheniformis.

  • Analyze phenotypic changes under various growth conditions to infer function.

  • Compare growth rates, stress responses, and metabolite production between wild-type and knockout strains .

• Precise Gene Editing:

  • Introduce specific mutations in functional domains to assess their importance.

  • Create domain swaps with homologous proteins to determine domain-specific functions.

  • Generate reporter fusions at the native locus for expression and localization studies.

• CRISPRi for Conditional Knockdown:

  • Implement CRISPR interference (CRISPRi) using catalytically inactive Cas9 (dCas9).

  • Design sgRNAs targeting different regions of the BLi00901 gene for variable repression.

  • Create inducible CRISPRi systems to control the timing of gene repression.

  • Monitor temporal changes in cellular physiology following knockdown.

• CRISPR-Based Screening:

  • Perform genome-wide CRISPR screens to identify genes genetically interacting with BLi00901.

  • Use synthetic genetic array (SGA) approaches with the BLi00901 knockout as a query strain.

  • Identify suppressor mutations that restore phenotypes in the absence of BLi00901.

What are common challenges in expressing recombinant BLi00901/BL05075 and how can they be addressed?

Based on general recombinant protein expression challenges and specific information from the search results, researchers may encounter the following issues:

How can inconsistencies in BLi00901/BL05075 activity assays be resolved?

When encountering inconsistencies in activity assays for BLi00901/BL05075 (once a functional assay is established), consider this systematic approach:

What statistical approaches are appropriate for analyzing BLi00901/BL05075 functional data?

For robust analysis of experimental data related to BLi00901/BL05075, consider these statistical approaches:

• Experimental Design Statistics:

  • Response Surface Methodology (RSM) for optimizing multiple parameters simultaneously, as demonstrated for other B. licheniformis proteins .

  • Plackett-Burman design for screening significant factors affecting protein expression or activity.

  • Central Composite Design (CCD) for detailed optimization of key parameters.

• Comparative Analysis:

  • Analysis of Variance (ANOVA) to assess differences between experimental conditions.

  • Student's t-test (paired or unpaired) for comparing two specific conditions.

  • Tukey's or Dunnett's post-hoc tests for multiple comparisons.

• Correlation and Regression Analysis:

  • Multiple linear regression to model relationships between experimental variables and measured outcomes.

  • Partial least squares (PLS) regression for handling multicollinearity in complex datasets.

  • Principal Component Analysis (PCA) for dimension reduction and identification of patterns in multivariate data.

• Time-Series Analysis:

  • Repeated measures ANOVA for time-course experiments.

  • Mixed-effects models to account for both fixed and random effects in longitudinal data.

  • Growth curve modeling for expression or activity kinetics studies.

How can I address solubility issues with recombinant BLi00901/BL05075?

The amino acid sequence of BLi00901/BL05075 suggests potential membrane association, which may lead to solubility challenges . To address these issues:

• Buffer Optimization:

  • Screen buffers with varying pH levels (typically pH 6.0-9.0) to identify optimal solubility conditions.

  • Test different salt concentrations (typically 100-500 mM NaCl) to minimize aggregation.

  • Evaluate the effect of additives known to enhance protein solubility:

    • Mild detergents (0.01-0.1% Triton X-100, NP-40, or CHAPS)

    • Stabilizing agents (5-10% glycerol, 1-5 mM DTT, 0.5-2 M urea)

    • Amino acid additives (50-500 mM arginine or proline)

• Expression Condition Modifications:

  • Reduce expression temperature (16-20°C) to slow protein synthesis and improve folding.

  • Decrease inducer concentration to reduce expression rate and prevent aggregation.

  • Co-express with molecular chaperones (GroEL/GroES, DnaK/DnaJ/GrpE) to assist proper folding.

• Protein Engineering Approaches:

  • Express as a fusion with solubility-enhancing tags (MBP, SUMO, Thioredoxin).

  • Design constructs with flexible linkers between domains.

  • Consider expressing individual domains separately if full-length protein remains insoluble.

• Refolding Strategies (if inclusion bodies form):

  • Develop a denaturation and refolding protocol using gradual dialysis or on-column refolding.

  • Optimize refolding buffer components including redox pairs for disulfide bond formation.

  • Implement step-wise reduction of denaturant concentration to improve folding efficiency.

What biosafety level is required for working with recombinant B. licheniformis expressing BLi00901/BL05075?

Bacillus licheniformis is classified as a Risk Group 1 organism according to NIH guidelines, indicating it is not associated with disease in healthy adult humans . Work with recombinant B. licheniformis expressing BLi00901/BL05075 would typically require:

• Biosafety Level 1 (BSL-1) Practices:

  • Standard microbiological practices.

  • Laboratory benchtop work with appropriate personal protective equipment (PPE).

  • Handwashing facilities must be available.

  • Work can be conducted on open benchtops with standard microbiology safety practices.

• Considerations for Recombinant Work:

  • While B. licheniformis itself is BSL-1, work with recombinant DNA should follow NIH Guidelines for Research Involving Recombinant or Synthetic Nucleic Acid Molecules .

  • B. licheniformis complies with OECD criteria for Good Industrial Large-Scale Practice (GILSP) microorganisms and meets criteria for safe production microorganisms .

• Institutional Requirements:

  • Work must be approved by the Institutional Biosafety Committee (IBC).

  • Documentation in the institution's electronic IBC platform is typically required .

  • Risk assessments should be performed before initiating work.

What NIH guidelines apply to research involving recombinant BLi00901/BL05075?

Research involving recombinant Bacillus licheniformis UPF0295 protein BLi00901/BL05075 falls under the NIH Guidelines for Research Involving Recombinant or Synthetic Nucleic Acid Molecules. Key points from the updated guidelines (effective September 30th, 2024) include :

• Classification and Containment:

  • B. licheniformis is classified as a Risk Group 1 organism, requiring BSL-1 containment measures .

  • Experiments involving recombinant or synthetic nucleic acids in B. licheniformis would typically fall under Section III-E or III-F of the NIH Guidelines.

• Institutional Oversight:

  • All research using recombinant or synthetic nucleic acids must be registered with the Institutional Biosafety Committee (IBC).

  • The IBC uses the NIH Guidelines to review all research that uses biological material and biohazards .

• Recent Updates:

  • The 2024 version includes new requirements for Gene Drive Modified Organisms (GDMOs), which would apply if BLi00901/BL05075 research incorporated gene drive technology.

  • The term "helper viruses" has been replaced with "helper systems" in the updated guidelines.

  • Certain viruses have been reclassified for consistency with the BMBL 6th edition .

What documentation is required for institutional biosafety committee approval when working with recombinant B. licheniformis?

When seeking Institutional Biosafety Committee (IBC) approval for work with recombinant B. licheniformis expressing BLi00901/BL05075, researchers should prepare the following documentation :

• Bioregistration Form:

  • Complete description of the recombinant construct, including vector maps and insert sequences.

  • Detailed experimental procedures and containment measures.

  • Risk assessment addressing potential hazards and mitigation strategies.

  • Information on the recipient strain (B. licheniformis) and its safety profile .

• Personnel Information:

  • Documentation of appropriate training for all personnel.

  • Verification of occupational health requirements.

  • Description of specific roles and responsibilities of team members.

• Facility Information:

  • Description of laboratory facilities to be used.

  • Verification that the facility meets BSL-1 requirements for work with B. licheniformis.

  • Equipment available for containment and decontamination.

• Experimental Design Documentation:

  • Detailed protocols for genetic manipulation procedures.

  • Description of expression systems and control measures.

  • Plans for safe handling and disposal of recombinant materials.

• GDMO Documentation (if applicable):

  • For any research that might involve gene drive technology, additional documentation on the eIBC platform would be required .

How should waste containing recombinant BLi00901/BL05075 be handled in a laboratory setting?

Proper waste management for materials containing recombinant B. licheniformis UPF0295 protein BLi00901/BL05075 should follow these guidelines:

• Liquid Waste:

  • Decontaminate all liquid cultures and supernatants containing recombinant B. licheniformis with appropriate disinfectant (e.g., 10% bleach solution for 30 minutes).

  • After decontamination, liquids can typically be disposed of down the drain with running water.

  • Document decontamination procedures according to institutional requirements.

• Solid Waste:

  • Contaminated solid materials (plates, tubes, pipette tips) should be collected in appropriate biohazard containers.

  • Autoclave all solid waste at 121°C for at least 30 minutes.

  • After autoclaving, waste can be disposed of as regular trash according to institutional guidelines.

• Sharps:

  • Collect in puncture-resistant sharps containers.

  • Decontaminate by autoclaving before disposal.

  • Follow institutional procedures for final disposal of treated sharps waste.

• Protein Preparation Waste:

  • Solutions containing purified recombinant BLi00901/BL05075 protein should be decontaminated chemically or by autoclaving.

  • Materials containing imidazole or other purification reagents may require special disposal considerations according to chemical waste regulations.

• Documentation Requirements:

  • Maintain waste disposal logs as required by institutional policies.

  • Follow any additional waste management requirements specified by the IBC approval.

  • Ensure all laboratory personnel are trained in proper waste management procedures.