Dataset Information

Isolation and biochemical characterization of LEAP-2, a novel blood peptide expressed in the liver.

ABSTRACT: The human genome contains numerous genes whose protein products are unknown in terms of structure, interaction partner, expression, and function. To unravel the function of these orphan genes, it is of particular value to isolate native forms of protein and peptide products derived from these genes. From human blood ultrafiltrate, we characterized a novel gene-encoded, cysteine-rich, and cationic peptide that we termed liver-expressed antimicrobial peptide 2 (LEAP-2). We identified several circulating forms of LEAP-2 differing in their amino-terminal length, all containing a core structure with two disulfide bonds formed by cysteine residues in relative 1-3 and 2-4 positions. Molecular cloning of the cDNA showed that LEAP-2 is synthesized as a 77-residue precursor, which is predominantly expressed in the liver and highly conserved among mammals. This makes it a unique peptide that does not exhibit similarity with any known human peptide regarding its primary structure, disulfide motif, and expression. Analysis of the LEAP-2 gene resulted in the identification of an alternative promoter and at least four different splicing variants, with the two dominating transcripts being tissue-specifically expressed. The largest native LEAP-2 form of 40 amino acid residues is generated from the precursor at a putative cleavage site for a furin-like endoprotease. In contrast to smaller LEAP-2 variants, this peptide exhibited dose-dependent antimicrobial activity against selected microbial model organisms. LEAP-2 shares some characteristic properties with classic peptide hormones and it is expected that the isolation of this novel peptide will help to unravel its physiological role.

SUBMITTER: Krause A

PROVIDER: S-EPMC2312392 | biostudies-literature | 2003 Jan

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Isolation and biochemical characterization of LEAP-2, a novel blood peptide expressed in the liver.

Krause Alexander A Sillard Rannar R Kleemeier Burkhard B Klüver Enno E Maronde Erik E Conejo-García José Ramon JR Forssmann Wolf Georg WG Schulz-Knappe Peter P Nehls Michael C MC Wattler Frank F Wattler Sigrid S Adermann Knut K

Protein science : a publication of the Protein Society 20030101 1

The human genome contains numerous genes whose protein products are unknown in terms of structure, interaction partner, expression, and function. To unravel the function of these orphan genes, it is of particular value to isolate native forms of protein and peptide products derived from these genes. From human blood ultrafiltrate, we characterized a novel gene-encoded, cysteine-rich, and cationic peptide that we termed liver-expressed antimicrobial peptide 2 (LEAP-2). We identified several circu ...[more]

PMID: 12493837

Similar Datasets

Project description:Diethylstilbestrol (DES) can adversely affect the immune system of developing fetuses or even elicit toxic responses such as nerve toxicity and genotoxicity in human beings, thereby warranting methods to remove DES from the environments. The present study characterized a novel DES-degrading Bacillus subtilis JF and analyzed the degradation metabolites. The strain was collected at the China General Microbiological Culture Collection Center (Collection number: CGMCC 7950). The environmental effects, such as DES concentrations, pH levels, and temperature, on the strain's degradation ability were tested. Degradation metabolites of DES by strain JF were analyzed via high performance liquid chromatography (HPLC) and liquid-chromatography time of flight mass spectrometry (LC-TOF-MS). Results indicated that B. subtilis JF can effectively degrade DES within a concentration of 25-200 mg/L. Increasing pH levels (pH > 7) are reported to increase the degradation rate of DES by the strain. The optimal temperature for strain JF to degrade DES was identified as 45°C. In this study, 4, 4'-hexene estrogen quinones (DESQ) and DES-4-semiquinone were speculated as two degradation metabolites of DES, and both can be completely degraded by strain JF. A slight reduction of DES in the blank system [DES cultured in Luria-Bertani (LB) medium without strain JF] was observed in this study. The reduction trend in the blank system only occurred during the first few days (about 4 days) and was considerably lesser than the decomposition and transformation effect of DES via strain JF. Furthermore, the metabolite DESQ could not be further decomposed in blank LB medium without strain JF. All the results demonstrate that complete degradation of DES in the fermentation broth occurs due to the function of strain JF rather than organic decomposition. In conclusion, the high efficiency of degradation and the potential to degrade DES completely indicates that strain JF has potential for the bioremediation of DES-contaminated environments (soil, river, and so on) and fermented foods.

Dataset Information

Isolation and biochemical characterization of LEAP-2, a novel blood peptide expressed in the liver.

Publications

Isolation and biochemical characterization of LEAP-2, a novel blood peptide expressed in the liver.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets