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Xanthoquinodins, new anticoccidial agents produced by Humicola sp. Production, isolation and physico-chemical and biological properties.

Humicola sp. FO-888, a soil isolate, was found to produce a series of new anticoccidial compounds. Five active compounds, designated xanthoquinodins A1, A2, A3, B1 and B2 were isolated from the fermentation broth of the producing strain by solvent extraction and HPLC. Xanthoquinodins inhibited the growth of Eimeria tenella in an in vitro assay system using BHK-21 cells as a host. No schizont in the cells was observed at concentrations of 0.02-0.2 micrograms/ml for xanthoquinodins A1, A3, B1 and B2 and at 0.02 micrograms/ml for xanthoquinodin A2.

Animals↗

Cell-free biosynthesis of cyclosporin A and analogues.

The final assembly of the 11-peptide chain of cyclosporins and its cyclization is accomplished in the producer Beauveria nivea by cyclosporine synthetase. This multienzyme represents the largest integrated enzyme structure reported so far. Its size has been estimated to approximately 1,500 kDa by SDS-PAGE. Some enzyme bound linear peptides could be isolated and identified. All of them represent partial sequences of cyclosporin A starting with D-alanine. These peptides were bound by thioester linkage to the enzyme. This could be demonstrated by liberation of the peptides with performic acid and by inhibition of in vitro cyclosporin A synthesis with thiol blocking agents. Cyclosporin synthetase is capable to synthesize besides a lot of cyclosporins known from fermentation studies some new cyclosporins so far not obtainable by fermentation. So, for example the synthesis of [N-methyl-(+)-2-amino-3-hydroxy-4,4-dimethyloctanoic acid1]CyA, Dihydro-CyA, [L-norvaline2,5, N-methyl-L-norvaline11]CyA, [L-allo-isoleucine5, N-methyl-L-allo-isoleucine11]CyA, [D-2-aminobutyric acid8]CyA, [beta-chloro-D-alanine8]CyA and some related compounds could be established. We were able to synthesize these cyclosporins in sufficient quantities to ensure their structure by fast atom bomdardment mass spectroscopy and to examine their immunosuppressitivity. All new cyclosporins synthesized in the in vitro system so far are immunosuppressive.

Amino Acid Sequence↗

Molecular structure and evolution of the conjugative multiresistance plasmid pRE25 of Enterococcus faecalis isolated from a raw-fermented sausage.

Plasmid pRE25 from Enterococcus faecalis transfers resistances against kanamycin, neomycin, streptomycin, clindamycin, lincomycin, azithromycin, clarithromycin, erythromycin, roxithromycin, tylosin, chloramphenicol, and nourseothricin sulfate by conjugation in vitro to E. faecalis JH2-2, Lactococcus lactis Bu2, and Listeria innocua L19. Its nucleotide sequence of 50237 base pairs represents the largest, fully sequenced conjugative multiresistance plasmid of enterococci (Plasmid 46 (2001) 170). The gene for chloramphenicol resistance (cat) was identified as an acetyltransferase identical to the one of plasmid pIP501 of Streptococcus agalactiae. Erythromycin resistance is due to a 23S ribosomal RNA methyl transferase, again as found in pIP501 (ermB). The aminoglycoside resistance genes are packed in tandem as in transposon Tn5405 of Staphylococcus aureus: an aminoglycoside 6-adenyltransferase, a streptothricin acetyl transferase, and an aminoglycoside phosphotransferase.). Identical resistance genes are known from pathogens like Streptococcus pyogenes, S. agalactiae, S. aureus, Campylobacter coli, Clostridium perfringens, and Clostridium difficile. pRE25 is composed of a 30.5-kbp segment almost identical to pIP501. Of the 15 genes involved in conjugative transfer, 10 codes for putative transmembrane proteins (e.g. trsB, traC, trsF, trsJ, and trsL). The enterococcal part is joined into the pIP501 part by insertion elements IS1216V of E. faecium Tn1545 (three copies), and homologs of IS1062 (E. faecalis) and IS1485 (E. faecium). pRE25 demonstrates that enterococci from fermented food do participate in the molecular communication between Gram-positive and Gram-negative bacteria of the human and animal microflora.

Animals↗

Nocathiacins, new thiazolyl peptide antibiotics from Nocardia sp. I. Taxonomy, fermentation and biological activities.

Thiazolyl peptide antibiotics, nocathiacin I, II and III, were identified in a culture of Nocardia sp. WW-12651 (ATCC 202099). They exhibit potent in vitro activity (ng/ml) against a wide spectrum of gram-positive bacteria, including multiple-drug resistant pathogens such as methicillin-resistant Staphylococcus aureus (MRSA), multi-drug resistant Enterococcus faecium (MREF) and fully penicillin-resistant Streptococcus pneumoniae (PRSP), and demonstrate excellent in vivo efficacy in a systemic Staphylococcus aureus infection mice model.

Animals↗

Sidedness of yeast plasma membrane vesicles and mechanisms of activation of the ATPase by detergents.

The binding of concanavalin A and of fluorescein 5'-isothiocyanate indicate similar amount of right-side-out and inside-out vesicles in plasma membrane vesicles from either glucose-starved or glucose-fermenting yeast cells. These vesicles contain low-activity and high-activity states of the ATPase, respectively. Unmasking of latent active sites can explain the limited ATPase activation (about 2-fold) produced by several detergents on both kinds of vesicles. On the other hand, lysophosphatidic acid (oleoyl) produces a 7-fold activation of the ATPase in vesicles from glucose-starved cells. This effect is accompanied by a change in Km of the enzyme and probably reflects a direct action of the detergent on the ATPase. A similar activation and Km change can be obtained by sonication of the vesicles, although in this case soybean phospholipids are required for maximal activity. Apparently the low-activity state of the yeast plasma membrane ATPase can be activated not only by glucose metabolism 'in vivo' (mechanism unknown) but also by some detergents and physical treatments 'in vitro'. Experiments with purified ATPase from glucose-starved cells also indicate that lysophosphatidic acid (oleoyl) specifically activates the enzyme. These results suggest a note of caution on considering the usual interpretation of the effects of detergents on membrane enzymes, which only take into account the unmasking of latent active sites.

Adenosine Triphosphatases↗

[The antioxidant effects of amtizol and trimetazidine].

Experiments were conducted on rats to study the antioxidant effects of amtisol and trimethasidin (25 mg/kg) in incomplete cerebral ischemia complicated by hypoxia. Amtisol as well as trimethasidin inhibited activation of lipid peroxidation (LPO) and prevented decrease in activity of the antioxidant system. In in vitro experiments amtisol and trimethasidin blocked epinephrine auto-oxidation. Amtisol inhibited ascorbate-dependent LPO in the liposomes and metabolizing model system, inhibited fermentative NADP-dependent POL in brain tissue homogenates.

Acute Disease↗

CHARACTERISTICS OF A STRAIN OF STAPHYLOCOCCUS AUREUS GROWN IN VIVO AND IN VITRO.

Beining, Paul R. (The Catholic University of America, Washington, D.C.) and E. R. Kennedy. Characteristics of a strain of Staphylococcus aureus grown in vivo and in vitro. J. Bacteriol. 85:732-741. 1963.-A comparative survey was conducted on the characteristics of a strain of Staphylococcus aureus after it had been grown in vitro (VSB) and after it had been collected from the peritoneal exudate of an infected guinea pig (GSB). Both VSB and GSB strains gave the same results when studied in an extensive series of tests, including bound and soluble coagulases, bacteriophage type, antibiotic-sensitivity pattern, the usual fermentation reactions, deoxyribonucleic acid base composition, and qualitative tests for hemolysins, deoxyribonuclease, ribonuclease, staphylokinase, staphyloprotease, lipase, and phosphatase. The in vivo strain differed significantly from the in vitro strain in respiratory rate, agar gel diffusion studies, agglutinability in tube tests, virulence tests in rabbits and mice, growth on tellurite-glycine agar, susceptibility to human gamma-globulin in agar, and in the quantitative production of deoxyribonuclease, alpha-hemolysin, leucocidin, and hyaluronidase.

Agar↗

Formate as an intermediate in the bovine rumen fermentation.

An average of 11 (range, 2 to 47) mumoles of formate per g per hr was produced and used in whole bovine rumen contents incubated in vitro, as calculated from the product of the specific turnover rate constant, k, times the concentration of intercellular formate. The latter varied between 5 and 26 (average, 12) nmoles/g. The concentration of formate in the total rumen contents was as much as 1,000 times greater, presumably owing to formate within the microbial cells. The concentration of formate in rumen contents minus most of the plant solids was varied, and from the rates of methanogenesis the Michaelis constant, K(m), for formate conversion to CH(4) was estimated at 30 nmoles/g. Also, the dissolved H(2) was measured in relation to methane production, and a K(m) of 1 nmole/g was obtained. A pure culture of Methanobacterium ruminantium showed a K(m) of 1 nmole of H(2)/g, but the K(m) for formate was much higher than the 30 nmoles for the rumen contents. It is concluded that nonmethanogenic microbes metabolize intercellular formate in the rumen. CO(2) and H(2) are the principal substrates for rumen methanogenesis. Eighteen per cent of the rumen methane is derived from formate, as calculated from the intercellular concentration of hydrogen and formate in the rumen, the Michaelis constants for conversion of these substrates by rumen liquid, and the relative capacities of whole rumen contents to ferment these substrates.

Animals↗

FK-506, a novel immunosuppressant isolated from a Streptomyces. I. Fermentation, isolation, and physico-chemical and biological characteristics.

FK-506, a novel immunosuppressant, has been isolated from the fermentation broth of Streptomyces tsukubaenis No. 9993 as colorless prism and the molecular formula was determined as C44H69NO12.H2O. The compound suppressed immune responses in vitro and in vivo with mice. This immunosuppressive effect was more potent than that of ciclosporin.

Animals↗

An in vitro evaluation of some unconventional ruminant feeds in terms of the organic matter digestibility, energy and microbial biomass.

In vitro organic matter apparent digestibility (IVOMAD), true digestibility (IVOMTD), metabolizable energy (ME), net energy lactation (NEL), microbial nitrogen (MN) and synthesis of microbial biomass (MBM) were estimated to predict the nutritive values of some agricultural by-products, drought-tolerant range plants and browses. The relationships between in vitro gas production (GP), and true or apparent digestibility. MN and MBM were studied utilizing an in vitro incubation technique. The values of IVOMAD, IVOMTD, ME, NEL, GP, MBM and MN varied with the studied experimental materials. The true fermentation of the outside part of Atriplex leucoclada produced a higher volume of gas than the middle or the inside parts, and this was associated with an increase in the values of IVOMAD, IVOMTD, ME and NEL. However, screening off the wood from olive cake to obtain olive cake pulp increased the IVOMAD, IVOMTD, ME, NEL and the volume of gas production from the true fermented material. One ml of gas was generated from the true degradation of 5 mg of wheat straw, Moringa oleifera, Alhagi camelorum, Eucaliptus camaldulensis and A. leucoclada, from 11 mg of Prosopsis stephaniana and olive cake pulp, and from 20 mg of olive cake or olive cake wood. The amount of MN or MBM produced from 100 mg of truly fermented organic matter depended on the kind of the fermented material and amounted to 0.7-2.9 mg or 8-34 mg, respectively. Crude fibre was negatively correlated to IVOMAD, IVOMTD, ME and NEL. Gas production was positively correlated to IVOMAD and IVOMTD but negatively correlated to MBM and MN.

Animal Feed↗

Effects of processing and in vitro proteolytic digestion on soybean and yambean hemagglutinins.

Some conventional processing methods were applied on yambean and soybean seeds and flour samples. They include soaking fermentation, cooking whole seeds in the presence and absence of trona, autoclaving and dry heat treatment of flour samples. Hemagglutinating activity was assayed for after processing treatments. The hemagglutinating proteins from these seeds were classified based on their solubility properties. Effects of the presence of 0.01% concentration of trypsin, pepsin and proteases on agglutination of human red blood cells were also evaluated. Most processing methods, particularly cooking whole seeds for 1-2 h, soaking and fermentation, reduced hemagglutinating activity on cow red blood cells. Size reduction accompanied by heat treatment was effective in eliminating hemagglutination. Both the albumin and globulin fractions of the soybean showed hemagglutinating activity but only the albumin fraction of the yambean had agglutinating properties. Proteolytic action of proteases was more effective in reduction of hemagglutinating activity than that of trypsin and pepsin.

Animals↗

Potent in vitro anticancer activity of metacycloprodigiosin and undecylprodigiosin from a sponge-derived actinomycete Saccharopolyspora sp. nov.

Bioassay-guided fractionation of CHCl3 extract from the fermentation broth of a sponge Mycale plumose-derived actinomycete Saccharopolyspora sp. nov., led to the isolation of two known prodigiosin analogs--metacycloprodigiosin (1) and undecylprodigiosin (2). These compounds exhibited significant cytotoxic activities against five cancer cell lines: P388, HL60, A-549, BEL-7402, and SPCA4. This is the first report on the significant cytotoxicity of metacycloprodigiosin (1) against human cancer cell lines.

Animals↗

Sourdough lactobacilli and celiac disease.

Celiac disease (CD) is one of the most common food intolerance. The only effective treatment for CD is a strict adherence to a gluten-free diet throughout the patient's lifetime. Gluten-free products are not widely available and are usually more expensive than their gluten-containing counterparts. There is, therefore, an urgent need to develop safe and effective therapeutic alternatives, to develop high-quality gluten-free products and to investigate the potential of the bread making biotechnology following ancient protocols which include long-time fermentation by selected sourdough lactic acid bacteria. This review describes the most relevant results related to biotechnologies that use selected sourdough lactic acid bacteria and probiotics as starters for sourdough fermentation to investigate their potential to decrease the risk of gluten contamination in gluten-free products. As shown by studies in vitro on celiac intestinal tissue and in vivo on CD patients, the bacterial proteolytic activity is rather promising not only as currently demonstrated for eliminating traces of contaminant gluten but probably also in perspective for the manufacture of tolerated baked goods.

Bread↗

Effect of direct-fed microbials on rumen microbial fermentation.

Nonbacterial, direct-fed microbials added to ruminant diets generally consist of Aspergillus oryzae fermentation extract, or Saccharomyces cerevisiae cultures, or both. Results from in vivo research have been variable regarding effects of direct-fed microbials on ruminant feedstuff utilization and performance. Some research has shown increased weight gains, milk production, and total tract digestibility of feed components, but others have shown little influence of direct-fed microbials on these parameters. In vitro research with mixed ruminal microorganisms likewise has been inconsistent regarding the effects of direct-fed microbials. Several researchers observed that direct-fed microbials increased cellulolytic bacterial numbers in the rumen and stimulated the production of some fermentation end products. This suggests that direct-fed microbials may be providing growth factors for the ruminal microbes. However, other researchers have reported no effect of direct-fed microbials on in vitro fiber digestion. Recent research demonstrated that growth of the predominant ruminal bacterium Selenomonas ruminantium in lactate medium as well as lactate uptake by whole cells of Sel. ruminantium were markedly increased by an A. oryzae fermentation extract and an S. cerevisiae culture. In addition, both products increased the production of acetate, propionate, succinate, total VFA, and cell yield (grams of cells per mole of lactate). Therefore, it appears that these direct-fed microbials provide soluble factors that stimulate lactate utilization by Sel. ruminantium. Evidence is presented indicating that the malate content of the A. oryzae fermentation extract and S. cerevisiae culture may be involved in this stimulation.

Animals↗

Ethanolic fermentation in transgenic tobacco expressing Zymomonas mobilis pyruvate decarboxylase.

During oxygen limitation in higher plants, energy metabolism switches from respiration to fermentation. As part of this anaerobic response the expression of genes encoding pyruvate decarboxylase (PDC) and alcohol dehydrogenase (ADH) is strongly induced. In addition there is ample evidence for post-translational regulation. In order to understand this multi-level regulation of the anaerobic response, we provided tobacco with the constitutive capacity of ethanolic fermentation by expressing a PDC gene derived from the obligate anaerobe Zymomonas mobilis. The protein accumulated to high levels and was active in an in vitro assay. During the first 2-4 h of anoxia, acetaldehyde accumulated to 10- to 35-fold and ethanol to 8- to 20-fold higher levels than in wild-type. Under normoxic conditions no accumulation of acetaldehyde and ethanol could be measured. Instead, the two products may be immediately re-metabolized in tobacco leaf tissue. We show that aerobic fermentation takes place when the respiratory system is inhibited. Although these conditions enhance ethanolic fermentation under normoxia, they fail to increase ADH transcript levels. These results indicate that anaerobic transcription is triggered not by the metabolic consequences of oxygen limitation, but directly through an oxygen-sensing system.

Acetaldehyde↗

New polyene antifungal antibiotic produced by a species of Actinoplanes.

A new species of Actinoplanes, which has been deposited with the designation NRRL 5325 at the Northern Utilization Research and Development Division of the U. S. Department of Agriculture, produces a polyene antifungal complex designated as Sch 16656. The complex, consisting of one major and three minor components, is isolated from the fermentation broth by a solvent extraction procedure and purified by precipitation methods. The major component is a heptaene and is highly active in vitro and in vivo against Candida albicans. It is active also against strains of Torulopsis and is significantly more potent orally than candicidin in mice against Candida infections.

Actinomycetales↗

[The role of enteric bacteria in childhood urinary tract infections and their in vitro response to antimicrobial agents].

In this study, 154 cases of suspected bacterial urinary tract infection were examined bacteriologically. Urine cultures yielded, E. coli in 84 patients Citrobacter in 22 (C. freundii: 9, C. diversus: 9) Proteus in 21 (P. vulgaris: 6, P. morgani: 4, P. rettgeri: 2. P. mirabilis: 4, lactose fermenting strains: 5), Pseudomonas in 12 (P. aeruginosa: 5, other strains of Pseudomonas: 7), Klebsiella in 9 (K. aerogenes: 3, K. pneumonia: 6) and Enterobacter in 6 patients (E. aerogenes: 1, E. cloacae: 5). In vitro antibiotic sensitivity tests showed that gentamicin, nalidixic acid, bactrim and gantrisin were the most effective antibacterial agents respectively. Multiple resistances was found in 39 strains of E. coli out of 84. In other species multiple resistance was found in varying degrees. It is concluded that. Every measure should be taken to eradicate the causative organisms in the urinary tract in children.

Anti-Bacterial Agents↗