Recombinant Yersinia enterocolitica serotype O:8 / biotype 1B UPF0059 membrane protein YE1772 (YE1772)

What is YE1772 and what are its basic structural characteristics?

YE1772 is a membrane protein belonging to the UPF0059 family found in Yersinia enterocolitica serotype O:8 / biotype 1B. The full-length recombinant protein consists of 189 amino acids and can be expressed with an N-terminal His tag in bacterial expression systems such as E. coli. The protein is classified as a membrane protein, indicating its localization within the bacterial cell membrane where it likely performs specific functions related to membrane integrity or transport. The UPF0059 designation indicates it belongs to a family of proteins with unknown function, representing an area of ongoing research interest. The availability of recombinant forms, such as the His-tagged version (product code RFL9243YF), facilitates research applications by enabling protein purification and characterization .

How does YE1772 compare to other membrane proteins in Yersinia species?

YE1772 belongs to the UPF0059 family of membrane proteins found in Yersinia enterocolitica, while other Yersinia species like Y. pestis express well-characterized membrane-associated proteins such as F1 and V antigens that have been extensively studied for their roles in virulence and as vaccine targets. The F1 and V antigens from Y. pestis have been successfully expressed in recombinant systems and evaluated for protective efficacy against plague infections . Unlike these well-characterized virulence factors, YE1772's function remains largely unexplored, presenting opportunities for comparative analysis between different Yersinia membrane proteins. Sequence alignment and structural prediction tools can be employed to identify conserved domains and potential functional similarities between YE1772 and other bacterial membrane proteins with known functions. Such comparative analyses may provide insights into the evolutionary relationships and functional conservation across Yersinia species.

What expression systems are most effective for producing functional recombinant YE1772?

For effective expression of recombinant YE1772, E. coli-based expression systems have demonstrated success as evidenced by commercially available recombinant YE1772 protein preparations . When expressing membrane proteins like YE1772, researchers should consider specialized E. coli strains designed for membrane protein expression, such as C41(DE3) or C43(DE3), which are engineered to accommodate the potential toxicity associated with overexpressing membrane proteins. Expression optimization typically requires testing various induction conditions (IPTG concentration, temperature, and duration) to balance protein yield with proper folding. For structural and functional studies requiring higher yields of properly folded protein, alternative expression systems might include yeast (Pichia pastoris) or insect cell systems which often provide better membrane protein folding environments. Addition of fusion partners such as the N-terminal His-tag facilitates purification while maintaining protein solubility and can be combined with solubility-enhancing tags like MBP (maltose-binding protein) for improved expression outcomes .

What are the optimal methods for purification and structural characterization of YE1772?

Purification of YE1772 typically begins with affinity chromatography using the N-terminal His-tag, employing nickel or cobalt resins under conditions that maintain membrane protein stability. Buffer optimization is critical, with detergents like n-dodecyl-β-D-maltoside (DDM) or lauryl maltose neopentyl glycol (LMNG) often proving effective for membrane protein solubilization while preserving native structure. For structural characterization, researchers should employ a multi-technique approach beginning with circular dichroism (CD) spectroscopy to assess secondary structure elements, followed by size exclusion chromatography to evaluate oligomeric state and homogeneity. For high-resolution structural analysis, X-ray crystallography remains challenging for membrane proteins, making cryo-electron microscopy (cryo-EM) increasingly valuable. For YE1772, researchers could adapt methodologies used in membrane protein-enriched extracellular vesicles (MPEEVs) platforms, which enable the study of membrane proteins in their native lipid environment and have successfully characterized other membrane proteins with electron cryomicroscopy and electron cryotomography at approximately 16 nm resolution .

How can membrane protein-enriched extracellular vesicles improve YE1772 research?

Membrane protein-enriched extracellular vesicles (MPEEVs) offer significant advantages for YE1772 research by providing a native-like membrane environment that maintains proper protein folding and topological orientation. This platform enables the study of YE1772 in its functional state, anchored in a lipid bilayer with correct transmembrane orientation. The MPEEV approach has demonstrated success with other membrane proteins, resulting in spherical vesicles approximately 100 nm in diameter that display proteins with their extracellular domains protruding outward in a radial fashion. These vesicles can be visualized using electron cryomicroscopy (cryo-EM) and electron cryotomography (cryo-ET) to characterize protein incorporation into the membrane and assess structural features with resolution sufficient to observe elongated protein spikes protruding from the membrane surface (approximately 12-16 nm) . An additional benefit of the MPEEV platform is remarkable stability, with vesicles remaining intact and suitable for imaging after storage at 4°C for over two months, providing practical advantages for longitudinal studies and collaborations requiring sample transport between facilities .

What analytical techniques best differentiate between functional and non-functional forms of YE1772?

To differentiate between functional and non-functional forms of YE1772, researchers should implement a combination of biophysical and functional assays. Thermal shift assays using differential scanning fluorimetry can assess protein stability under various buffer conditions, with functional protein typically exhibiting higher thermal stability. Size exclusion chromatography coupled with multi-angle light scattering (SEC-MALS) provides information on oligomeric state and monodispersity, important indicators of properly folded membrane proteins. For direct functional assessment, researchers should develop binding assays to identify potential interaction partners or ligands, such as surface plasmon resonance (SPR) or microscale thermophoresis (MST). Reconstitution into proteoliposomes followed by function-specific assays (e.g., transport assays if YE1772 has transporter properties) provides the most definitive functional characterization. For structural validation, limited proteolysis can distinguish between properly folded and misfolded proteins, as the former typically shows distinct proteolytic patterns reflecting protected structural domains, while misfolded proteins often display random digestion patterns.

What are the hypothesized functions of YE1772 based on sequence homology?

The UPF0059 family designation of YE1772 indicates it belongs to a group of proteins with uncharacterized function, presenting challenges for functional prediction. Sequence analysis using tools like BLAST, Pfam, and InterPro may reveal conserved domains shared with proteins of known function in other bacterial species. Membrane localization suggests potential roles in processes such as nutrient transport, signal transduction, or maintenance of membrane integrity. Computational approaches including protein-protein interaction predictions and co-expression analysis with other genes of known function can provide additional functional insights. Structural homology modeling based on crystallized membrane proteins with similar topologies may reveal structural features consistent with specific functions such as pore formation or substrate binding. Given the pathogenic nature of Yersinia enterocolitica, YE1772 may also play roles in virulence, host interaction, or survival within host environments, warranting comparison with virulence-associated membrane proteins from related pathogens like the F1 and V antigens in Y. pestis .

How might YE1772 be utilized in vaccine development research?

YE1772 could serve as a potential vaccine target against Yersinia enterocolitica infections, following approaches similar to those used for Y. pestis antigens. Research would begin with immunogenicity assessment through animal studies measuring antibody responses to purified YE1772 protein or YE1772-expressing constructs. For vector-based vaccine development, researchers could adapt methodologies used for Y. pestis vaccines, where raccoon poxvirus (RCN) vectors expressing F1 and V antigens have shown efficacy against plague. These vectors can simultaneously express multiple antigens, as demonstrated by the dual antigen construct RCN-F1/V307, which provided comparable protection to co-administration of single antigen constructs . Evaluation of YE1772-based vaccines would require challenge studies in appropriate animal models, assessing protection against various Y. enterocolitica strains. Additionally, researchers should investigate cross-protection against different serotypes and biotypes to determine vaccine breadth. The potential for YE1772 to serve as part of a multi-component vaccine containing additional Yersinia antigens should also be explored to enhance protective efficacy .

What experimental approaches can determine if YE1772 plays a role in antibiotic resistance?

To investigate YE1772's potential role in antibiotic resistance, researchers should implement a comprehensive experimental approach beginning with gene knockout or knockdown studies using CRISPR-Cas9 or antisense RNA technology. These modified strains would undergo minimum inhibitory concentration (MIC) testing with a panel of antibiotics to identify sensitivity changes compared to wild-type bacteria. Complementary overexpression studies could determine if elevated YE1772 levels confer increased resistance to specific antibiotics. Membrane permeability assays using fluorescent dyes (e.g., SYTO9/propidium iodide) would assess if YE1772 affects antibiotic entry into bacterial cells. Direct interaction between YE1772 and antibiotics could be evaluated through techniques like isothermal titration calorimetry or surface plasmon resonance. For mechanistic insights, transport assays with proteoliposomes containing purified YE1772 would determine if the protein actively transports antibiotics across membranes. Researchers should also investigate YE1772 expression levels in clinical isolates with varying antibiotic resistance profiles using qRT-PCR and western blotting to establish correlations between expression levels and resistance phenotypes.

How does YE1772 compare between different Yersinia enterocolitica serotypes?

Comparative analysis of YE1772 across different Y. enterocolitica serotypes requires sequence alignment studies to identify conservation levels and polymorphic regions. While specific data on YE1772 variation is limited in the provided search results, approaches similar to those used in Y. pestis antigen research can be applied. Researchers should isolate and sequence the ye1772 gene from multiple clinical and environmental isolates representing different serotypes (particularly O:3, O:8, and O:9) and biotypes. Sequence variations should be analyzed for their impact on protein structure and potential functional differences using computational prediction tools. Expression analysis using qRT-PCR and western blotting can determine if YE1772 expression levels differ between serotypes under various growth conditions. Functional comparisons of recombinant YE1772 proteins from different serotypes could reveal serotype-specific behaviors relevant to pathogenesis or environmental adaptation. Additionally, researchers should investigate if certain YE1772 variants correlate with clinical outcomes or geographical distribution patterns, potentially identifying associations with virulence or transmission efficiency.

How do post-translational modifications affect YE1772 function and immunogenicity?

Post-translational modifications (PTMs) can significantly impact membrane protein function and immunogenicity, though specific data on YE1772 PTMs is not provided in the search results. To investigate PTMs in YE1772, researchers should purify the native protein from Y. enterocolitica cultures and analyze it using mass spectrometry techniques such as liquid chromatography-tandem mass spectrometry (LC-MS/MS). Comparison between native and recombinant YE1772 expressed in E. coli would identify differences in modification patterns, as bacterial expression systems like E. coli often lack the machinery for certain PTMs present in the native organism . Functional studies comparing native and recombinant proteins could reveal the impact of PTMs on protein activity. For immunogenicity assessment, researchers should compare antibody responses against native versus recombinant YE1772, with particular attention to whether PTMs create or mask immunologically relevant epitopes. Site-directed mutagenesis of predicted PTM sites would provide direct evidence of their functional importance. Additionally, investigations into how environmental conditions and growth phases affect YE1772 PTM patterns could reveal regulatory mechanisms controlling protein function during infection or stress responses.

What are the challenges in developing high-resolution structures of YE1772?

Developing high-resolution structures of membrane proteins like YE1772 presents significant challenges that require specialized approaches. Membrane proteins are notoriously difficult to crystallize due to their hydrophobic transmembrane domains and conformational flexibility. For YE1772 specifically, researchers must optimize detergent selection for solubilization while maintaining native protein folding and function. Traditional X-ray crystallography requires formation of well-ordered crystals, which often necessitates extensive screening of hundreds of crystallization conditions with various detergents and lipids. Cryo-electron microscopy (cryo-EM) offers an alternative approach that has revolutionized membrane protein structural biology, potentially allowing visualization of YE1772 in its native-like environment. The membrane protein-enriched extracellular vesicles (MPEEVs) platform described in the literature has successfully enabled cryo-EM visualization of membrane proteins with structural features extending approximately 12-16 nm from the membrane surface . For smaller membrane proteins like YE1772, researchers might need to employ strategies such as fusion with larger protein partners or antibody fragments to increase molecular weight and enable more accurate particle picking and alignment during cryo-EM data processing.

How can computational approaches enhance understanding of YE1772 structure-function relationships?

Computational approaches offer powerful tools for elucidating YE1772 structure-function relationships, particularly given the experimental challenges associated with membrane protein research. Modern protein structure prediction algorithms, especially those implementing deep learning like AlphaFold2, can generate reliable structural models of membrane proteins that serve as starting points for functional hypothesis generation. Molecular dynamics simulations can model YE1772's behavior within lipid bilayers, revealing conformational dynamics, potential ligand binding sites, and interaction with membrane lipids. These simulations typically require high-performance computing resources and specialized force fields optimized for membrane protein-lipid interactions. Computational docking studies can identify potential binding partners or substrates by virtually screening compound libraries against predicted binding pockets. For functional annotation, researchers should employ tools that integrate structural predictions with evolutionary conservation analysis, identifying functionally important residues conserved across species. Computational approaches should be validated through experimental methods such as site-directed mutagenesis of predicted functional residues followed by activity assays. Integration of computational predictions with experimental data through iterative cycles will provide the most comprehensive understanding of YE1772 structure-function relationships.

What is the potential role of YE1772 in multicomponent vaccine development compared to established Yersinia antigens?

The development of multicomponent vaccines incorporating YE1772 alongside established Yersinia antigens presents a promising research direction, potentially enhancing protective efficacy against Y. enterocolitica infections. When considering YE1772's role in such vaccines, researchers can draw parallels from successful approaches with Y. pestis antigens. Studies with Y. pestis have demonstrated that dual-antigen constructs expressing both F1 and V307 antigens within a single vector (RCN-F1/V307) provide protection comparable to simultaneous administration of individual constructs (RCN-F1 + RCN-V307) . Based on this precedent, researchers could develop similar constructs expressing YE1772 alongside other Y. enterocolitica antigens. The proven efficacy of dual-antigen Y. pestis vaccines against both wild-type and F1-negative strains suggests that multicomponent approaches provide broader protection against variant strains . This is particularly relevant for YE1772, as inclusion in multicomponent vaccines might address potential antigenic variation across Y. enterocolitica serotypes. Experimental evaluation would require comparing protection levels between single-antigen YE1772 vaccines and multicomponent formulations through appropriate animal challenge models, with attention to protection duration, antibody titers, and efficacy against diverse Y. enterocolitica strains.

What expression yields can be expected when producing recombinant YE1772?

Expression yields for recombinant YE1772 will vary significantly based on the expression system and optimization parameters employed. While specific yield data for YE1772 is not provided in the search results, researchers can expect yields comparable to other bacterial membrane proteins of similar size. The table below provides estimated yields based on comparable membrane protein expression systems:

To optimize expression, researchers should systematically vary induction parameters, including inducer concentration, temperature, and duration. Additionally, incorporating fusion partners such as MBP or SUMO can enhance solubility, while codon optimization of the ye1772 gene for the expression host can address potential rare codon usage issues. For membrane proteins like YE1772, expression in specialized E. coli strains such as C41(DE3) or C43(DE3) often yields better results due to their adaptation to membrane protein overexpression toxicity .

How does research on YE1772 compare with studies on other Yersinia membrane proteins?

Research on YE1772 appears less advanced compared to extensively studied Yersinia membrane proteins, particularly those from Y. pestis. This comparative analysis table highlights key differences:

This comparison highlights the research gap for YE1772 despite its potential significance. While Y. pestis F1 and V antigens have progressed to advanced vaccine candidates with demonstrated protection in multiple animal models including mice and prairie dogs, YE1772 remains at earlier research stages . The established methodologies for Y. pestis antigens provide valuable frameworks that can be adapted for accelerating YE1772 research, particularly regarding expression optimization, immunogenicity assessment, and protective efficacy evaluation .

What protection levels could be expected from YE1772-based vaccines based on comparable Yersinia antigen vaccines?

While specific protection data for YE1772-based vaccines is not available in the search results, insights can be drawn from protection levels achieved with other Yersinia antigen vaccines, particularly those targeting Y. pestis. The table below summarizes protection data from Y. pestis vaccine studies that could inform expectations for YE1772-based vaccines:

Based on these data, researchers developing YE1772-based vaccines might reasonably target protection rates of 50-80% in mouse models and 60-85% in larger animal models following optimization of vaccination protocols. The data also indicates that booster vaccinations significantly improve protection rates, increasing from 60% to 85% in prairie dog models . Importantly, these studies demonstrate that protection can be maintained for extended periods (270 days), suggesting durable immunity might be achievable with properly formulated YE1772 vaccines. Additionally, the ability of dual-antigen constructs to protect against variant strains (F1-negative Y. pestis) suggests that YE1772-based vaccines might similarly provide cross-protection against variant Y. enterocolitica strains when combined with other antigens .