Ethnomedicinal and traditional uses of the Ferns of Khyber Pakhtunkhwa, Pakistan

Ferns are often used by indigenous people in Khyber Pakhtunkhwa, Pakistan. This study was designed to collect the ethnomedicinal and traditional knowledge of these locals about this group of vascular plants. Forty taxa belong to nineteen genera and ten families are used in the treatment of different diseases. The Pteridaceae was the most representative family with twelve taxa (30%), followed by Athyriaceae and Dryopteridaceae with six taxa each (30%), and Thelypteridaceae with five taxa (12.5%). Regarding the genera, Adiantum, Asplenium and Dryopteris ranked first with four taxa each (30%), followed by Aleuritopteris, Diplazium, Pteris and Equisetum with three taxa each (30%), followed by Athyrium, Oeosporangium, Polystichum and Pseudophegopteris with two taxa each (20%). These taxa were commonly used in the treatment of respiratory disorders i.e. asthma, bronchitis, emphysema, pneumonia; intestinal ulcer, stomach, urinary ailments and skin disorders by the methods of decoction and infusion. Traditional knowledge about ethnomedicinal plants is a valuable and essential source for the discovery of allopathic, herbal and homeopathic medicines.

Development of serological proteome analysis of mastitis by Staphylococcus aureus in ewes

Staphylococcus aureus is a major agent of mastitis in ruminants worldwide. So far, efficient measures for its prophylaxis (including vaccination) have proven to be unsuccessful and there is a need for a better understanding of the host response to udder infection by S. aureus. Serological proteome analysis (SERPA) is a promising technique that can be used to identify S. aureus immuno-dominant determinants providing that bacterial culture conditions used to grow S. aureus strains for protein sample preparation mimic the context of mastitis. A S. aureus strain was used in experimental mastitis to generate sheep serum used to determine the best growth conditions for SERPA. Sera collected in the field from different ewes suffering from mastitis by S. aureus were used to confirm experimental observations. Three different culture media (BHI, whey and iron-depleted RPMI) were tested. The influence of aeration and growth phase on protein production was also evaluated by immuno-detection of protein samples prepared from cultures grown in different conditions and obtained from different culture fractions (supernatant, cell wall, and total lysates). Our results showed that culturing in iron-depleted RPMI with (secreted proteins, prepared from stationary phase) or without aeration (cell wall proteins, prepared from early stationary phase, and total proteins, prepared from exponential phase) is the condition that best mimics growth in vivo during mastitis and this in vitro growth condition is to be used henceforth in experiments involving SERPA.

GAPDH, a novel regulator of the pro-apoptotic mitochondrial membrane permeabilization

Glyceraldehyde-3-phosphate dehydrogenase (GAPDH) is a pleiotropic enzyme that is overexpressed in apoptosis and in several human chronic pathologies. Here, we report that the protein accumulates in mitochondria during apoptosis, and induces the pro-apoptotic mitochondrial membrane permeabilization, a decisive event of the intrinsic pathway of apoptosis. GAPDH was localized by immunogold labeling and identified by matrix-assisted laser desorption/ionization-time of flight and nano liquid chromatography mass spectroscopy/mass spectroscopy in the mitochondrion of various tissues and origins. In isolated mitochondria, GAPDH can be imported and interact with the voltage-dependent anion channel (VDAC1), but not the adenine nucleotide translocase (ANT). The protein mediates a cyclosporin A-inhibitable permeability transition, characterized by a loss of the inner transmembrane potential, matrix swelling, permeabilization of the inner mitochondrial membrane and the release of two pro-apoptotic proteins, cytochrome c and apoptosis-inducing factor (AIF). This novel function of GAPDH might have implications for the understanding of mitochondrial biology, oncogenesis and apoptosis.

Preparation of patients for anaesthesia - achieving quality care

Implementation of anaesthesia begins with a preoperative assessment of the surgical patient and development of an anaesthetic plan. Preparation of the patient includes the preoperative assessment, review of preoperative tests, optimisation of medical conditions, adequate preoperative fasting, appropriate premedication, and the explanation of anaesthetic risk to patients. The goals of preoperative preparation are to reduce the morbidity of surgery, to increase the quality while decreasing the cost of perioperative care, and to return the patient to desirable functioning as quickly as possible. A knowledgeable anaesthesiologist is the 'final clinical gatekeeper', who coordinates perioperative management and ensures that the patient is in the optimal state for anaesthesia and surgery.

Propionibacteria induce apoptosis of colorectal carcinoma cells via short-chain fatty acids acting on mitochondria

The genus Propionibacterium is composed of dairy and cutaneous bacteria which produce short-chain fatty acids (SCFA), mainly propionate and acetate, by fermentation. Here, we show that P. acidipropionici and freudenreichii, two species which can survive in the human intestine, can kill two human colorectal carcinoma cell lines by apoptosis. Propionate and acetate were identified as the major cytotoxic components secreted by the bacteria. Bacterial culture supernatants as well as pure SCFA induced typical signs of apoptosis including a loss of mitochondrial transmembrane potential, the generation of reactive oxygen species, caspase-3 processing, and nuclear chromatin condensation. The oncoprotein Bcl-2, which is known to prevent apoptosis via mitochondrial effects, and the cytomegalovirus-encoded protein vMIA, which inhibits apoptosis and interacts with the mitochondrial adenine nucleotide translocator (ANT), both inhibited cell death induced by propionibacterial SCFA, suggesting that mitochondria and ANT are involved in the cell death pathway. Accordingly, propionate and acetate induced mitochondrial swelling when added to purified mitochondria in vitro. Moreover, they specifically permeabi-lize proteoliposomes containing ANT, indicating that ANT can be a critical target in SCFA-induced apoptosis. We suggest that propionibacteria could constitute probiotics efficient in digestive cancer prophylaxis via their ability to produce apoptosis-inducing SCFA.

Biochemical and antigenic characterisation of Mycoplasma gallisepticum membrane proteins P52 and P67 (pMGA)

Two membrane proteins from the avian pathogen Mycoplasma gallisepticum have been previously purified using a simple, efficient and non-denaturing method: a lipoprotein P67 (pMGA) and P52. In the current study, the lipid part of P67 was chemically analysed. The molecular structure of the lipoprotein-lipid component was determined to be S-glyceryl cysteine with two O-ester-linked acyl chains. Fatty acid analysis of the purified P67 indicated a heterogeneous composition: palmitic acid (16:0)>stearic acid (18:0)>oleic acid (18:1c)>myristic acid (14:0), with 16:0 as the major component. These findings, along with previously published results, support the conclusion that P67 is pMGA1.2, a true membrane-associated lipoprotein although not N-acylated. In contrast to P67, P52 is not a lipoprotein. Topological experiments using in situ treatment with proteases and growth inhibition in the presence of anti-P52 serum provided evidence of the surface exposition of the polypeptide. The N-terminal sequence of P52 was found to be similar to the dihydrolipoamide acetyltransferase from several mollicutes; this enzyme is a membrane-associated component of the pyruvate dehydrogenase complex. Immunoblotting techniques revealed that the surface antigens P52 and P67 were specific to the species M. gallisepticum and the closely related species M. imitans. No antigenic difference was revealed within these species with the anti-P52 serum, while anti-P67 serum confirmed the antigenic variability of P67. The potential of P52 and P67 as antigens in serological diagnosis tests or as candidates for anti-mycoplasma subunit vaccines is discussed.

Comparison of different electrophoretic separations of hen egg white proteins

The hen egg white protein composition has not yet been fully defined. To improve the knowledge of this biological fluid, the most usual and recently developed electrophoretic methods have been used: SDS-PAGE, native-PAGE, isoelectric focusing (IEF), and 2-dimensional electrophoresis (2DE). Seven of the major known proteins were thus identified in at least one electrophoretic system. Isoforms of ovotransferrin, ovalbumin, and ovomucoid were visualized when pI was used for the separation. Two-dimensional electrophoresis allowed separation of a very large number of spots. In each of the four systems, some components were revealed but not identified, and unknown spots were particularly numerous with 2DE. With this technique, many spots corresponding to small acidic proteins were highlighted, among which was the Ch21 protein, whose presence in hen egg white was thus confirmed. This study thus constitutes, to our knowledge, the first proteomic investigation of hen egg white.

Changes in protein synthesis and morphology during acid adaptation of Propionibacterium freudenreichii

Survival of bacteria in changing environments depends on their ability to adapt to abiotic stresses. Microorganisms used in food technology face acid stress during fermentation processes. Similarly, probiotic bacteria have to survive acid stress imposed within the stomach in order to reach the intestine and play a beneficial role. Propionibacteria are used both as cheese starters and as probiotics in human alimentation. Adaptation to low pH thus constitutes a limit to their efficacy. Acid stress adaptation in the probiotic SI41 strain of Propionibacterium freudenreichii was therefore investigated. The acid tolerance response (ATR) was evidenced in a chemically defined medium. Transient exposure to pH 5 afforded protection toward acid challenge at pH 2. Protein neosynthesis was shown to be required for optimal ATR, since chloramphenicol reduced the acquired acid tolerance. Important changes in genetic expression were observed with two-dimensional electrophoresis during adaptation. Among the up-regulated polypeptides, a biotin carboxyl carrier protein and enzymes involved in DNA synthesis and repair were identified during the early stress response, while the universal chaperonins GroEL and GroES corresponded to a later response. The beneficial effect of ATR was evident at both the physiological and morphological levels. This study constitutes a first step toward understanding the very efficient ATR described in P. freudenreichii.

A human TATA binding protein-related protein with altered DNA binding specificity inhibits transcription from multiple promoters and activators

The TATA binding protein (TBP) plays a central role in eukaryotic and archael transcription initiation. We describe the isolation of a novel 23-kDa human protein that displays 41% identity to TBP and is expressed in most human tissue. Recombinant TBP-related protein (TRP) displayed barely detectable binding to consensus TATA box sequences but bound with slightly higher affinities to nonconsensus TATA sequences. TRP did not substitute for TBP in transcription reactions in vitro. However, addition of TRP potently inhibited basal and activated transcription from multiple promoters in vitro and in vivo. General transcription factors TFIIA and TFIIB bound glutathione S-transferase-TRP in solution but failed to stimulate TRP binding to DNA. Preincubation of TRP with TFIIA inhibited TBP-TFIIA-DNA complex formation and addition of TFIIA overcame TRP-mediated transcription repression. TRP transcriptional repression activity was specifically reduced by mutations in TRP that disrupt the TFIIA binding surface but not by mutations that disrupt the TFIIB or DNA binding surface of TRP. These results suggest that TFIIA is a primary target of TRP transcription inhibition and that TRP may modulate transcription by a novel mechanism involving the partial mimicry of TBP functions.

Sorting of PC2 to the regulated secretory pathway in AtT20 cells

PC2 and PC3 are neuroendocrine specific members of the eukaryotic subtilisin-like proprotein convertase (PC) family. Both are sorted via the regulated secretory pathway into secretory granules. In order to identify sequences in PC2 which are involved in targeting to the regulated secretory pathway we expressed a series of PC2 cDNAs containing mutations in the C terminal or propeptide domains in the mouse corticotrophic AtT20 cell line. Sorting of endogenous PC3 was used as a control. PC2 and PC3 were secreted with similar kinetics and sorted to secretory granules with similar efficiencies. Deletions of up to 50 amino acids from the C-terminus of proPC2 had no effect on secretion or sorting, but larger deletions completely prevented maturation or secretion. Two large deletions within the propeptide also prevented secretion. Smaller deletions between the primary and secondary cleavage sites, or of the primary cleavage site, reduced the amount of protein secreted but did not affect sorting to secretory granules. Replacement of the propeptide of PC2 with that of the endogenous PC3 also had no effect on secretion or sorting. The results indicate that targeting of proPC2 to the regulated secretory pathway is dependent on more than one region within the proPC2 molecule.

The propeptide of prohormone convertase PC2 acts as a transferable aggregation and membrane-association signal

Prohormone convertase 2 (PC2) is a subtilisin-like protease involved in the intracellular processing of prohormones and proneuropeptides. Like its substrates, it is synthesised as a prepropeptide which undergoes proteolysis during transit through the regulated secretory pathway. Previous studies have shown that aggregation and membrane association of proPC2 occurs in a calcium-dependent and pH-dependent manner and that the pro-region of PC2 may be involved in this process. These events may be involved in the sorting of proteins to the regulated secretory pathway. To investigate this further, we made a chimeric protein containing both the signal peptide and pro-region of PC2 and the N-terminal part of alpha1-antitrypsin, called pro2alpha1. PC2, alpha1-antitrypsin and pro2alpha1 were compared with regard to their membrane association and aggregation properties using, respectively, sucrose gradient centrifugation after expression in Xenopus oocytes, and an in vitro aggregation assay. The chimeric protein, pro2alpha1, underwent low-pH-dependent aggregation and membrane association similar to wild-type PC2. Membrane association occurred at pH 5.5 in the absence of calcium and at pH 6.0 in the presence of 10 mM calcium but not at pH 6.5 or 7.0. alpha1-antitrypsin, as expected of a constitutively secreted protein, did not aggregate at low pH, nor associate with membranes. Pro2alpha1 thus exhibits the membrane association and aggregation properties of PC2, confirming the role of the pro-region in these processes. A series of deletions were performed within the 84-residue propeptide in order to define the sequences involved. Deletion of amino acids 52-77 reduced aggregation but large deletions in the pro-region had only a minimal effect on membrane association. These data suggest that several regions within the propeptide are important in these events.

Purification of Mycoplasma gallisepticum membrane proteins p52, p67 (pMGA), and p77 by high-performance liquid chromatography

The plasma membrane of the avian pathogen Mycoplasma gallisepticum contains about 200 polypeptides including the major lipoprotein pMGA. We have developed a simple and efficient procedure for the purification of three membrane proteins of this wall-less bacterium. Proteins were selectively extracted from isolated plasma membranes with the mild zwitterionic detergent (N-dodecyl-N,N-dimethylammonio) undecanoate (DDMAU) and subjected to size-exclusion chromatography (FPLC) in the presence of the same detergent. Two of the thus separated protein fractions were subjected to a third step involving an anion-exchange chromatography (HPLC), also in the presence of DDMAU, which led to the purification to homogeneity of p67, the major acyl protein of M. gallisepticum plasma membrane (yield, 40%; purification factor, 11), p52 (yield, 38%; purification factor, 20), and p77 (yield, approximately 45%; purification factor, 500). Analyses performed by Western blotting and crossed immunoelectrophoresis showed that the three purified proteins are distinct antigens. Furthermore, N-terminal sequencing confirmed that p67 is pMGA. The method described in this paper is simple, efficient, and nondenaturing; it provides pure proteins, at the milligram level for p52 and p67, and should prove easy to being scaled-up if necessary.

Selective acylation of plasma membrane proteins of Mycoplasma mycoides subsp. mycoides SC, the contagious bovine pleuropneumonia agent

The plasma membrane of Mycoplasma mycoides subsp. mycoides SC (strain KH3J) contains over 160 polypeptides with apparent molecular masses ranging from 14 to 125 kDa and isoelectric point values (pIs) from 5 to 9. In vivo labeling with [14C]-fatty acids revealed about 35 acylated polypeptides including the two major components p42 and p65 and displaying pIs between 5.5 and 9.0, with a majority between 6.5 and 8. The amphiphilic nature of most of these acyl proteins was confirmed by Triton X-114 phase partitioning. Gas-liquid chromatography analyses showed that the order of preference for protein acylation was 16:0 > 18:2c > 18:1c > 18:0 > 14:0, with 16:0 being the major O-ester-bound fatty acyl chain and 18:2c the major N-linked chain. The presence of S-glycerylcysteine and a ratio of [O-ester-bound acyl chains + N-linked chains]/O-ester bound chains of approximately 1.2 in M. mycoides subsp. mycoides SC membrane proteins are consistent with a lipid modification similar to that occurring in lipoproteins of Gram-negative eubacteria that contain an N-terminal acyl S-glycerylcysteine.

Acylation and immunological properties of Mycoplasma gallisepticum membrane proteins

The acylation of Mycoplasma gallisepticum membrane proteins was studied by electrophoresis after in vivo labelling with different 14C-fatty acids and by chemical analysis. The immunological properties of these proteins were investigated by Western blotting and crossed immunoelectrophoresis. Among the ca. 200 membrane polypeptides resolved by two-dimensional electrophoresis, 35 components (including the major protein p67) were covalently modified with acyl chains. These acylated proteins displayed lower pls than average (5.0-7.4 vs. 5.0-9.0) and proved to be the major membrane protein antigens and immunogens of M. gallisepticum. The apparent selectivity of fatty acid incorporation into proteins was, as suggested by in vivo labelling: palmitic acid (16:0) > myristic acid (14:0) > oleic acid (18:1c) > stearic acid (18:0) > linoleic acid (18:2c). However, the true order of selectivity, as revealed by chemical analysis, proved to be 18:2c > 16:0 > 18:1c > 18:0 > 14:0. More specifically, palmitic acid was the major O-ester-bound fatty acid and linoleic acid the major amide-linked fatty acid. The observed average ratio [O-ester-bound + amide-linked acyl chains]/O-ester-bound chains approximately 1.4 and the presence of S-glycerylcysteine suggest that, in M. gallisepticum, membrane proteins are lipid-modified according to a mechanism identical to that depicted for lipoproteins of Gram-negative eubacteria.

Evaluation of the efficacy of zwitterionic dodecyl carboxybetaine surfactants for the extraction and the separation of mycoplasma membrane protein antigens

The ability to extract mycoplasma membrane protein antigens using the alkyl carboxybetaine surfactants (N-dodecyl-N,N-dimethylammonio)butyrate (DDMAB, CMC = 4.3 mM) and (N-dodecyl-N,N-dimethylammonio)undecanoate (DDMAU, CMC = 0.13 mM) was assessed by protein titration and SDS-PAGE analysis. The maximum yields of membrane protein solubilization ranged from 20 to 90%, depending upon both the mycoplasma membrane investigated and the surfactant used. In five of six cases, the extraction was optimal for surfactant concentrations of ca. 25 mM. DDMAB displayed a higher efficiency in membrane protein extraction. The order of efficiency for both surfactants was Spiroplasma melliferum > Acholaplasma laidlawii > Mycoplasma gallisepticum. In contrast, DDMAU proved much more selective. The order of selectivity was M. gallisepticum > S. melliferum > A. laidlawii. The highest selectivity was recorded for the major proteins p67 and spiralin of M. gallisepticum and S. melliferum, respectively. For p67, notably, DDMAU proved superior to 10 other surfactants. Dot immunobinding and crossed immunoelectrophoresis analyses showed that both dodecyl carboxybetaines were suitable as membrane protein-solubilizing agents in immunological techniques. Furthermore, these surfactants did not exhibit effects adverse to the activity of A. laidlawii membrane NADH oxidase. One promising application of DDMAU is the separation of membrane proteins by ion-exchange HPLC as illustrated by the good resolution of M. gallisepticum membrane proteins and purification of p67 to almost homogeneity. These data show that dodecyl carboxybetaine surfactants are useful for the extraction of mycoplasma membrane antigens under mild conditions.(ABSTRACT TRUNCATED AT 250 WORDS)