Recombinant production of antimicrobial peptides in Escherichia coli: a review.

Antimicrobial peptides are of great interest due to their potential application as novel antibiotics. Large quantities of highly purified peptides are required to meet the needs of basic research and clinical trials. Compared with isolation from natural sources and chemical synthesis, recombinant approach offers the most cost-effective means for large-scale peptide manufacture.

Copulatory courtship behavior and sine song as a mate recognition cue in Drosophila lini and its sibling species.

Most Drosophila species sing species-specific pulse songs during their "precopulatory courtship." Three sibling species of the Drosophila montium species subgroup performed "copulatory courtship": males generated courtship songs by vibrating either wing only after mounting and during copulation. In these three species, strong sexual isolation was detected between D.

The tandem affinity purification technology: an overview.

Tandem affinity purification (TAP) is a methodology for the isolation of protein complexes from endogenous sources. It involves incorporation of a dual-affinity tag into the protein of interest and introduction of the construct into desired cell lines or organisms. Using the two affinity handles, the protein complex assembled under physiological conditions, which contains the tagged target protein and its interacting partners, can be isolated by a sequential purification scheme.

Larval metamorphosis of the mussel Mytilus galloprovincialis Lamarck, 1819 in response to neurotransmitter blockers and tetraethylammonium.

The metamorphic response of pediveliger larvae of Mytilus galloprovincialis to the neurotransmitter blockers chlorpromazine, amitriptyline, rauwolscine, idazoxan, atenolol and butoxamine, and to tetraethylammonium chloride (TEA) was investigated through a series of bioassays. Chlorpromazine, amitriptyline and idazoxin inhibited larval metamorphosis induced by 10⁻⁴ M epinephrine. The concentration that inhibited metamorphosis by 50% (IC₅₀) for chlorpromazine and amitriptyline was 1.

Self-cleaving fusion tags for recombinant protein production.

Fusion expression is a common practice for recombinant protein production. Some fusion tags confer solubility on the target protein whereas others provide affinity handles that facilitate purification. However, the tag usually needs to be removed from the final product, which involves using expensive proteases or hazardous chemicals and requires additional chromatography steps.

Highly efficient purification of protein complexes from mammalian cells using a novel streptavidin-binding peptide and hexahistidine tandem tag system: application to Bruton's tyrosine kinase.

Tandem affinity purification (TAP) is a generic approach for the purification of protein complexes. The key advantage of TAP is the engineering of dual affinity tags that, when attached to the protein of interest, allow purification of the target protein along with its binding partners through two consecutive purification steps. The tandem tag used in the original method consists of two IgG-binding units of protein A from Staphylococcus aureus (ProtA) and the calmodulin-binding peptide (CBP), and it allows for recovery of 20-30% of the bait protein in yeast.

Specialized compartments of cardiac nuclei exhibit distinct proteomic anatomy.

As host to the genome, the nucleus plays a critical role as modulator of cellular phenotype. To understand the totality of proteins that regulate this organelle, we used proteomics to characterize the components of the cardiac nucleus. Following purification, cardiac nuclei were fractionated into biologically relevant fractions including acid-soluble proteins, chromatin-bound molecules and nucleoplasmic proteins.

Stress signaling by Tec tyrosine kinase in the ischemic myocardium.

Nonreceptor tyrosine kinases have an increasingly appreciated role in cardiac injury and protection. To investigate novel tasks for members of the Tec family of nonreceptor tyrosine kinases in cardiac phenotype, we examined the behavior of the Tec isoform in myocardial ischemic injury. Ischemia-reperfusion, but not cardiac protective agents, induced altered intracellular localization of Tec, highlighting distinct actions of this protein compared with other isoforms, such as Bmx, in the same model.

Convolutional perfectly matched layer for elastic second-order wave equation.

In this work, a method is presented to extend the convolutional perfectly matched layer (C-PML) to simulate acoustic wave propagation in elastic media with a second-order equation formulation. This non-physical layer is used at the computational edge of a finite element method algorithm in frequency domain, and a pseudo-spectral algorithm in time domain, as an absorbing boundary condition (ABC) to truncate unbounded media. Numerical results show that the C-PML ABC attenuates the outgoing surface waves more effectively than classical PML ABC as proposed by Berenger [J.

Commonly used tag combinations for tandem affinity purification.

TAP (tandem affinity purification) allows rapid and clean isolation of a tagged protein along with its interacting partners from cell lysates. Initially developed in yeast, the TAP method has subsequently been adapted to other cells and organisms. In combination with MS analysis, this method has become an indispensable tool for systematic identification of target-associated protein complexes.

[Cost-effectiveness and cost-benefit analysis on the integrated schistosomiasis control strategies with emphasis on infection source in Poyang Lake region].

Objective: To evaluate the cost-effectiveness and cost-benefit on the integrated schistosomiasis control strategies with emphasis on infection source, and provide scientific basis for the improvement of schistosomiasis control strategy.

Methods: Aiguo and Xinhe villages in Jinxian County were selected as intervention group where the new comprehensive strategy was implemented, while Ximiao and Zuxi villages in Xinzi County served as control where routine control program was implemented. New strategy of interventions included removing cattle from snail-infested grasslands and providing farmers with farm machinery, improving sanitation by supplying tap water and building lavatories and methane gas tanks, and implementing an intensive health education program.

A haplotype of the catalase gene confers an increased risk of essential hypertension in Chinese Han.

Our previous study in an isolated population showed an association between a genetic variant in the catalase gene (CAT) and essential hypertension (EH). This study indicates that three variants in the promoter and 5'-UTR region of CAT are predominant in Chinese Han, and they form two major haplotypes. A case-control study showed that the CATH2 haplotype confers susceptibility to EH (Pgenotype=0.

The role of antimicrobial peptides in cardiovascular physiology and disease.

Antimicrobial peptides are natural peptide antibiotics, existing ubiquitously in both plant and animal kingdoms. They exhibit broad-spectrum antimicrobial activity and play an important role in host defense against invading microbes. Recently, these peptides have been shown to possess activities unrelated to direct microbial killing and be involved in the complex network of immune responses and inflammation.

Molecular and functional characterization of a c-type lysozyme from the Asian corn borer, Ostrinia furnacalis.

Some lepidopteran lysozymes have been reported to display activity against Gram-positive and Gram-negative bacteria, in contrast to most lysozymes that are active only against Gram-positive bacteria. OstrinLysC, a c-type lysozyme, was purified from the Asian corn borer, Ostrinia furnacalis Guenée (Lepidoptera: Pyralidae), and shows activity against Gram-positive and Gram-negative bacteria. The NH2-terminal amino acid sequence was determined by Edman degradation and used in a homology cloning strategy.

Carrier proteins for fusion expression of antimicrobial peptides in Escherichia coli.

Antimicrobial peptides are an essential component of innate immunity and play an important role in host defence against microbial pathogens. They have received increasing attention recently as potential novel pharmaceutical agents. To meet the requirement for necessary basic science studies and clinical trials, large quantities of these peptides are needed.

Bactrocerin-1: a novel inducible antimicrobial peptide from pupae of oriental fruit fly Bactrocera dorsalis Hendel.

A novel antimicrobial peptide, Bactrocerin-1, was purified and characterized from an immunized dipteran insect, Bactrocera dorsalis. Bactrocerin-1 has 20 amino acid residues with a mass of 2,325.95 Da.

RAPD: a database of recombinantly-produced antimicrobial peptides.

We have developed the Recombinantly-produced Antimicrobial Peptides Database (RAPD) to house relevant information on recombinant approaches to generate antimicrobial peptides. Key information stored in the database, which is extracted from published experiments, includes expression host, fusion strategy, release method and yield for individual peptides. Bibliographic data directly related to each particular case are also available.

Five tyrosines and two serines in human albumin are labeled by the organophosphorus agent FP-biotin.

Tyrosine 411 of human albumin is an established site for covalent attachment of 10-fluoroethoxyphosphinyl- N-biotinamidopentyldecanamide (FP-biotin), diisopropylfluorophosphate, chlorpyrifos oxon, soman, sarin, and dichlorvos. This work investigated the hypothesis that other residues in albumin could be modified by organophosphorus agents (OP). Human plasma was aggressively treated with FP-biotin; plasma proteins were separated into high and low abundant portions using a proteome partitioning antibody kit, and the proteins were digested with trypsin.

On-resin cleavage of bacterially expressed fusion proteins for purification of active recombinant peptides SK-29, KR-20, LL-29, and LL-23 from human sweat or skin.

Post-translational processing of host defense cathelicidin peptide LL-37 in human sweat and skin generates new antimicrobial peptides. To understand structure and mechanism of action of these LL-37 derivatives, this article presents the cloning and expression of SK-29, KR-20, LL-29, and LL-23. We also provide a two-step chromatographic purification protocol of general use.

A novel method for purifying recombinant human host defense cathelicidin LL-37 by utilizing its inherent property of aggregation.

The importance of human LL-37 in host defense and innate immunity is well appreciated as reflected by an exponential increase of relevant literature in Pub-Med. Although several articles reported the expression and purification of this cathelicidin, some protocols suffered from low efficiency in enzyme cleavage of fusion proteins due to aggregation and poor separation of recombinant LL-37 from the carrier protein on reverse-phase HPLC. We present a new method for purifying LL-37 that avoids both problems.

Effect of mu-opioid receptor gene polymorphisms on heroin-induced subjective responses in a Chinese population.

Background: Genetic factors that influence subjective responses to drug use (such as euphoria) contribute to the risk of addiction. mu-opioid receptor is the molecular target of heroin mediating its effects in both pain relief and euphoria.

Methods: To evaluate the association of mu-opioid receptor gene (OPRM1) variants with heroin-induced positive responses on first use, we studied 336 Chinese Han heroin addicts recruited in Shanghai and divided heroin addicts into two groups (positive vs.

NMR studies of aurein 1.2 analogs.

Aurein 1.2 is an antimicrobial and anticancer peptide isolated from an Australian frog. To improve our understanding of the mechanism of action, two series of peptides were designed.

Dopamine D4 receptor polymorphism modulates cue-elicited heroin craving in Chinese.

Rationale: Subjective craving, which contributes to the continuation of drug use in active abuser and the occurrence of relapse in detoxified abusers, is considered to be a central phenomenon in addiction. Dopamine pathway has been implicated in the mechanism underlying the cue-elicited craving for a variety of addictive substances.

Objectives: The objective of this study was to test the hypothesis that heroin addicts carrying D4 dopamine receptor gene (DRD4) variable number tandem repeat (VNTR) long type allele would have higher craving after exposure to a heroin-related cue.

Solution structures of human LL-37 fragments and NMR-based identification of a minimal membrane-targeting antimicrobial and anticancer region.

To understand the structure and activity relationship of human LL-37, a series of peptide fragments was designed. The N-terminal fragment, LL-37(1-12), was not active, while the C-terminal fragment, LL-37(13-37), killed Escherichia coli, as well as drug-sensitive and drug-resistant cancer cells. A 13-residue core antibacterial and anticancer peptide, corresponding to residues 17-29 of LL-37, was identified based on total correlated spectroscopy by trimming nonessential regions (TOCSY-trim).

The effect of dopamine D2, D5 receptor and transporter (SLC6A3) polymorphisms on the cue-elicited heroin craving in Chinese.

Heroin dependence is resulted from the interaction between multiple genetic and environmental factors. Subjective craving is considered to be a central phenomenon, which contributes to the continuation of drug use in active abuser and the occurrence of relapse in detoxified abusers. Dopamine pathway has been implicated in the cue-elicited craving for a variety of addictive substances.