Recombinant Human KLK11 Protein: Biology & Research Guide

Recombinant Human KLK11 Protein is a recombinantly produced member of the kallikrein-related peptidase family, a serine protease of significant interest in oncology, biomarker discovery, and proteolytic cascade research.

Protein Family

Kallikrein-related peptidase (KLK) family

Enzyme Class

Serine protease

Gene Name

KLK11

Species Origin

Human (Homo sapiens)

Product SKU

rp366220

Research Areas

Oncology, biomarker research, proteolytic cascades

What Is KLK11? Biological Background

Kallikrein-related peptidase 11 (KLK11), also known as hippostasin or TLSP (trypsin-like serine protease), is a secreted serine protease encoded by the KLK11 gene, which is located on chromosome 19q13.4 within the kallikrein gene locus — the largest contiguous cluster of serine protease genes in the human genome.

KLK11 belongs to the kallikrein-related peptidase (KLK) family, a group of 15 structurally related, secreted serine proteases (KLK1–KLK15). These enzymes share a conserved catalytic triad of histidine, aspartate, and serine residues and are involved in diverse physiological processes including skin desquamation, seminal liquefaction, neural function, and tissue remodeling.

KLK11 exhibits trypsin-like proteolytic activity, cleaving peptide bonds C-terminal to basic amino acid residues (arginine and lysine). It is expressed in a variety of tissues including the prostate, brain, testis, and salivary glands, and its expression is subject to hormonal regulation, particularly by steroid hormones such as androgens and estrogens.

KLK11 Expression, Structure, and Biochemical Properties

The KLK11 gene encodes a preproprotein that undergoes post-translational processing: a signal peptide directs secretion, and the propeptide region is cleaved to generate the mature, active protease. This zymogen activation mechanism is a common feature shared across the KLK family and contributes to the tight spatial and temporal regulation of proteolytic activity in vivo.

Structurally, KLK11 adopts the canonical chymotrypsin fold characteristic of serine proteases, with a two-beta-barrel domain architecture surrounding the catalytic triad (His, Asp, Ser). The substrate-binding pocket (S1 site) confers trypsin-like specificity, accommodating positively charged residue side chains.

Recombinant Human KLK11 Protein (SKU: rp366220) is produced using recombinant DNA technology, enabling researchers to obtain a well-defined, reproducible protein preparation suitable for in vitro biochemical and cell-based assays. Recombinant production allows for consistent lot-to-lot quality, defined activity, and freedom from contaminating human-derived pathogens.

Research Applications of Recombinant Human KLK11 Protein

Recombinant Human KLK11 Protein is a versatile research tool used across several key areas of biomedical investigation:

• Oncology and Biomarker Research: KLK11 has been investigated as a potential tissue and serum biomarker in prostate, ovarian, and other cancers. Elevated or dysregulated KLK11 expression has been observed in certain malignancies, making recombinant KLK11 useful for developing and validating immunoassays (ELISA, Western blot) and as a calibrator or positive control in diagnostic assay development.
• Enzyme Substrate and Inhibitor Studies: Recombinant KLK11 enables the identification and characterization of physiological substrates and the screening of protease inhibitors, which may have therapeutic relevance in cancers and inflammatory conditions.
• Proteolytic Cascade Research: KLK11 participates in KLK activation cascades relevant to skin biology and potentially other tissues. Recombinant protein supports mechanistic studies of these cascades in vitro.
• Antibody Production and Validation: Recombinant KLK11 can serve as an immunogen for antibody generation and as a reference standard for antibody specificity validation.
• Structural Biology: Purified recombinant KLK11 can support crystallography, cryo-EM, or other structural studies to delineate substrate recognition determinants.

Handling, Storage, and Quality Considerations

To ensure optimal performance of Recombinant Human KLK11 Protein (rp366220), researchers should observe the following best practices:

• Storage: Store lyophilized or liquid formulations according to the datasheet specifications. In general, recombinant proteins should be stored at −20°C or −80°C (depending on formulation) and avoid repeated freeze-thaw cycles that can compromise activity and structural integrity. Refer to the product datasheet for confirmed storage conditions for rp366220.
• Reconstitution: When reconstituting lyophilized protein, use the buffer recommended in the datasheet and allow the vial to equilibrate to room temperature before opening. Gently mix; do not vortex vigorously.
• Activity Validation: Prior to use in critical experiments, verify protease activity using an appropriate fluorogenic peptide substrate assay. Confirm protein integrity by SDS-PAGE or Western blot.
• Carrier Protein: BSA or other carrier proteins may be included in formulations to enhance stability; consult the datasheet to avoid interference in downstream assays.
• Biosafety: Although recombinant and not derived directly from human tissue, standard good laboratory practices (GLP) should be followed when handling the protein.

For lot-specific activity data, purity assessments, and endotoxin levels, refer to the Certificate of Analysis (CoA) provided with each shipment.

Frequently asked questions

What is the biological function of KLK11?

KLK11 is a secreted serine protease with trypsin-like activity, cleaving substrates at the C-terminal side of arginine and lysine residues. It is implicated in a range of physiological processes including tissue remodeling, skin desquamation cascades, and hormonal signaling pathways, and has been studied as a potential cancer biomarker in prostate and ovarian malignancies.

What research applications is Recombinant Human KLK11 Protein (rp366220) suitable for?

Recombinant Human KLK11 Protein is suitable for a broad range of applications including enzyme activity and inhibitor screening assays, biomarker assay development and validation (e.g., ELISA), antibody production and specificity testing, in vitro substrate identification studies, and structural biology investigations. Always verify the specific validated applications in the product datasheet.

How should Recombinant Human KLK11 Protein be stored to maintain activity?

Recombinant Human KLK11 Protein should be stored according to the conditions specified in the product datasheet, typically at −20°C or −80°C. Repeated freeze-thaw cycles should be avoided to prevent loss of activity; consider aliquoting the protein upon first use. Refer to the Certificate of Analysis for lot-specific stability information.

Is Recombinant Human KLK11 Protein supplied in active or zymogen form?

The form (active enzyme vs. zymogen/inactive precursor) of the supplied Recombinant Human KLK11 Protein (rp366220) should be confirmed by consulting the product datasheet or Certificate of Analysis. Many commercial recombinant kallikrein preparations are supplied in the active form; however, researchers should verify this detail prior to designing activity-dependent assays.

References

1. Diamandis EP, Yousef GM. Human tissue kallikreins: a family of new cancer biomarkers. Clin Chem. 2002;48(8):1198-1205. PMID:12142373
2. Yousef GM, Diamandis EP. The new human tissue kallikrein gene family: structure, function, and association to disease. Endocr Rev. 2001;22(2):184-204. PMID:11294823
3. Paliouras M, Diamandis EP. Intracellular signaling pathways regulate hormone-dependent kallikrein gene expression. Tumour Biol. 2008;29(3):149-159.

Products are supplied for research and development use only. Not for use in humans, animals, diagnosis, or therapy.