Isolation and description of a non-motile,fusiform, stalked bacterium,a representatieve of a new genus

A single strain representing the fusiform group of caulobacters first described by Henrici and Johnson has been isolated from a freshwater pond. Like the genusCaulobacter this is a chemo-organotrophic bacterium that has one polar prostheca, a stalk in the sense that its apical holdfast permits the cell to attach to solid substrates. Fine structure studies reveal, however, that the prostheca of this organism contains typical cellular constituents, not the membranous material found in the stalks ofCaulobacter andAsticcacaulis. The organism also differs from the other caulobacters in having no motile stage and no dimorphic life cycle (both daughter cells are stalked at the time of division). Because only one strain has been isolated no nomenclatural proposals are made, but sufficient evidence is presented to indicate that this is a representative of a new genus of the Schizomycetes.     

Purification, cloning, and characterization of a profibrinolytic plasminogen-binding protein, TIP49a

The plasminogen receptors responsible for enhancing cell surface-dependent plasminogen activation expose COOH-terminal lysines on the cell surface and are sensitive to proteolysis by carboxypeptidase B (CpB). We treated U937 cells with CpB, then subjected membrane fractions to two-dimensional gel electrophoresis followed by ligand blotting with (125)I-plasminogen. A 54-kDa protein lost the ability to bind (125)I-plasminogen after treatment of intact cells and was purified by two-dimensional gel electrophoresis and then sequenced by mass spectrometry. Two separate amino acid sequences were obtained and were identical to sequences contained within human and rat TIP49a. The cDNA for the 54-kDa protein matched the human TIP49a sequence, and encoded a COOH-terminal lysine, consistent with susceptibility to CpB. Antibodies against rat TIP49a recognized the plasminogen-binding protein on two-dimensional Western blots of U937 cell membranes. Human (125)I-Glu-plasminogen bound specifically to TIP49a protein, and binding was inhibited by epsilon-aminocaproic acid. A single class of binding sites was detected, and a K(d) of 0.57 +/- 0.14 microm was determined. TIP49a enhanced plasminogen activation 8-fold compared with the BSA control, and this was equivalent to the enhancement mediated by plasmin-treated fibrinogen. These results suggest that TIP49a is a previously unrecognized plasminogen-binding protein on the U937 cell surface.     

Gastrointestinal stromal tumors in a baboon, a spider monkey, and a chimpanzee and a review of the literature

Background  Gastrointestinal stromal tumors (GISTs) are believed to originate from the intestinal pacemaker cells (interstitial cells of Cajal) or their progenitor cells. Spontaneous tumors have been reported in dogs, horses, rhesus, and a chimpanzee and they have been produced experimentally in mice and rats. GISTs represent a diagnostic challenge because they cannot be differentiated from non-lymphoid mesenchymal tumors without using human c-kit (CD117) immunohistochemistry.
Methods  Three neoplasms were incidental findings at necropsy in the stomachs of a baboon and a spider monkey and in the rectum of a chimpanzee.
Results  The GISTs were initially diagnosed grossly and histologically with hematoxylin and eosin as leiomyomas. Immunohistochemical analysis revealed that all three were c-kit (CD117) positive.
Conclusions  These are the first reports of GISTs in the baboon and spider monkey and the second in a chimpanzee. The occurrence of GISTs in non-human primates may provide a unique opportunity to study these tumors.     

Study of a novel glycoconjugate, thiopeptidoglycan, and a novel polysaccharide lyase, thiopeptidoglycan lyase

A typical filamentous bacterium, Sphaerotilus natans, secretes a thiolic glycoconjugate which is assembled into a microtube, so called sheath. The glycoconjugate is known to consist of a pentasaccharide-dipeptide repeating unit, but its chemical structure has not been completely elucidated. In order to determine its chemical structure, the sheath was broken down by performic acid oxidation. The released sulfonated derivative was water soluble which was suitable for detailed NMR analysis. The data exhibited the presence of two stoichiometric and one substoichiometric (relative abundance was about 0.5) acetylations, suggesting that the glycoconjugate is composed of two equimolar pentasaccharide-dipeptide repeating units each having either two or three acetyl groups. However, the position of substoichiometric acetylation could not be defined. To determine the position, the sheath was derivatized with a thiol selective fluorescent reagent followed by digestion with a specific polysaccharide lyase prepared from a sheath-degrading bacterium, Paenibacillus koleovorans. As expected, two fluorescent digests were recovered by reverse-phase HPLC and were subjected to NMR analysis. The data revealed that both digests are pentasaccharide-dipeptides which have unsaturated glucuronic acid and galactosamine residues at their reducing and non-reducing ends, respectively. It was also confirmed that one digest has 3-O-acetylated glucose residue while the other has non-derivatized glucose residue. The substoichiometric acetylation was thus identified with the 3-O-acetylation, and structural determination of the thiolic glycoconjugate was completed. By virtue of the clarification of the two digests' structures, the cleavage site was specified as (1→4)-α-galactosaminic bond to glucuronic acid. Based on the present and earlier findings, we propose a novel glycoconjugate category named thiopeptidoglycan and a novel polysaccharide lyase named thiopeptidoglycan lyase.     

Children's Television,Radio, Internet,and Computer Usage in a City and a Village of China

A first step in understanding media consumption is to understand the time people spend using media, and how usage varies across demographic groups and in response to other factors. While there is ample research from the West, research from China is less evident. Here I provide a case study of children's media usage in a rural and an urban area in China. The findings showed that a greater proportion of children in the urban sample used media such as television, Internet, and computer games, and that rural–urban residency had the most significant influence on television viewing. Further, more urban children reported their parents had concerns about media usage, whereas a greater proportion of children in the rural area had televisions in their bedrooms and ate meals while watching television. This difference was explained by differences in socio-economic levels, traditional values, and educational background. The findings show that the rural–urban difference, and other factors such as parental concern, should be considered when conducting and interpreting media consumption. There also are implications for health because a large proportion of children in the present study had televisions in their bedrooms and ate while watching television, and such behaviors in the West have been associated with unhealthy lifestyles.     

Isolation, Identification, and Characterization of a Lipoate-Degrading Pseudomonad and of a Lipoate Catabolite

A strain of bacteria that can degrade lipoic acid was isolated from soil. The bacterium, adapted to use 0.4% dl-lipoate as the sole organic substrate to supply carbon, sulfur, and energy, was identified morphologically and physiologically as a strain of Pseudomonas putida. Degradation of 1,6-(14)C-lipoic acid, synthesized from 1,6-(14)C-adipic acid, was evidenced by: (i) loss of approximately 50% of the total radioactivity from the medium after bacterial growth; (ii) appearance of (14)C-degradation products upon paper and thin-layer chromatography of the culture medium; and (iii) oxygraphically measured utilization of O(2) by cells in the presence of lipoate or other oxidizable substrates. Analyses of the benzene extract of culture medium by infrared, nuclear magnetic resonance, and mass spectrometry, and by gas-liquid chromatography after desulfuration, have characterized bisnorlipoic acid, or 4,6-dithiohexanoic acid, as the major catabolite present in the medium. beta-Oxidation of the side chain is thus proven to be a pathway employed by the pseudomonad to degrade lipoic acid.     

Construction, Expression, and Characterization of a Thermostable Xylanase

A hybrid gene, btx, encoding a thermostable xylanase, Btx, was constructed by substituting the 31 N-terminal amino acid residues of the Thermomonospora fusca xylanase A (TfxA) for the corresponding region of 22 amino acid residues of the Bacillus subtilis xylanase A (BsxA). The btx gene was expressed in Escherichia coli BL21. The halo size produced by xylanase Btx on a Remanzol brilliant blue R (RBB) xylan plate at 60°C and pH 6.0 was larger than those of BsxA and TfxA. The molecular weight of Btx was 22 kDa. Temperature and pH optima for Btx were at 50–60°C and 6.0, respectively. Btx showed activity over 80% over a pH range of 5.0–9.0, which was wider than that of BsxA, and was also more acid-resistant than TfxA. Btx exhibited significant thermostability compared with BsxA. The results show the importance of the N-terminal sequence of TfxA in thermostability.     

An allotypic specificity presumably of the a series in rabbit immunoglobulins, different from a1, a2, and a3

From the serum of a wild rabbit lacking all the known allotypic specificities of the a series, IgG showing an allotypic specificity named. A100 has been isolated and antisera against it prepared in domestic rabbits. The determinants responsible for the A100 allotypic specificity are present both on IgG and IgM. They are located on the heavy chain and the Fab fragment of IgG.Evidence for the genetic determinism of A100 suggests that it is the product of a new allele at the $\text{a}$ locus.     

Ending a decade of deception: a valiant failure, a not-so-valiant failure, and a success story

Prior studies involving two methods, Brooks Parsimony Analysis (BPA) and TreeMap, have found BPA to be the more reliable method. Recent criticisms leveled at these studies argue that the tests were unfairly created and biased in favor of BPA. The authors of a recent critique offered new exemplars to demonstrate flaws in BPA, plus a simple fix to correct the flaws found in TreeMap. A re‐evaluation of their exemplars clearly shows that the authors' calculations are incorrect, their understanding of the methods is lacking, and that their simple fix does not work. Additional analyses using TreeMap 2.02 are run to show that TreeMap 2.02, like TreeMap 1.0, cannot adequately deal with widespread parasites, contrary to the claims of its supporters. Furthermore, the exemplars corroborate previous findings that BPA, when calculated correctly, is more reliable than TreeMap1.0 and TreeMap 2.02 and therefore the method of choice in coevolutionary and biogeographic studies.     

Isolation, Identification, and Characterization of a Feather-Degrading Bacterium

A feather-degrading culture was enriched with isolates from a poultry waste digestor and adapted to grow with feathers as its primary source of carbon, sulfur, and energy. Subsequently, a feather-hydrolytic, endospore-forming, motile, rod-shaped bacterium was isolated from the feather-degrading culture. The organism was Gram stain variable and catalase positive and demonstrated facultative growth at thermophilic temperatures. The optimum rate of growth in nutrient broth occurred at 45 to 50°C and at pH 7.5. Electron microscopy of the isolate showed internal crystals. The microorganism was identified as Bacillus licheniformis PWD-1. Growth on hammer-milled-feather medium of various substrate concentrations was determined by plate colony count. Maximum growth (approximately 10⁹ cells per ml) at 50°C occurred 5 days postinoculation on 1% feather substrate. Feather hydrolysis was evidenced as free amino acids produced in the medium. The most efficient conditions for feather fermentation occurred during the incubation of 1 part feathers to 2 parts B. licheniformis PWD-1 culture (10⁷ cells per ml) for 6 days at 50°C. These data indicate a potential biotechnique for degradation and utilization of feather keratin.     

Pyridinoline, a non-reducible crosslink of collagen. Quantitative determination, distribution, and isolation of a crosslinked peptide

Pyridinoline is a crosslink compound isolated from bovine Achilles tendon collagen. It is a 3-hydroxypyridinium derivative with three amino and three carboxyl groups (Fujimoto, D., Akiba, K., & Nakamura, N. (1977) Biochem. Biophys. Res. Commun. 76, 1124-1129). The contents of pyridinoline in collagens from various sources were determined. The pyridinoline content of bovine Achilles tendon was 0.16 residue per 1,000 residues and that of rat Achilles tendon collagen was 0.017 residue per 1,000 residues. Besides Achilles tendon collagens, pyridinoline was found in collagens from costal cartilage, rib and femoral bone of rat. It was not found in collagens from the tail tendon and skin of rat. A crosslinked, triple-chained peptide containing pyridinoline was isolated from bovine Achilles tendon collagen after digestion with pronase. Its amino acid composition suggests that the peptide may be involved in an intermolecular crosslink among a carboxyterminal sequence, a sequence near the aminoterminus and a sequence in the helical region.     

The Initiation, Growth, and Characteristics of a Tissue 2

The rate and extent of initiation of callus from potato tuberdiscs depends on the concentrations of auxin and kinetin inthe medium on which they are grown. NAA is the most effectiveauxin, initiating callus at a concentration (0. 01 mg/1) anorder of magnitude lower than for IAA or 2,4-D. There is a week'slag before initiation begins with IAA or 2,4-D. In combinationwith each auxin, kinetin is inhibitory to initiation of callusand its growth on the explant. High-intensity light and lowtemperature are also inhibitory. In isolated callus subcultured so as to prevent dilution ofits accumulated auxin, the only effect of varying exogenousauxin levels is as a progressive inhibition by NAA. If thisdilution is permitted, however, 2,4-D and IAA have an optimumgrowth promoting activity at 1 mg/1, whereas the effect of NAAincreases up to 10 mg/1. The growth of the callus is affectedby agar concentration (1 per cent optimum), and is halted bypH values below 5. The callus grows on various carbon sourcesbut is dependent upon one or more components of N. Z. Amine;it also requires a number of micronutrients. A suspension culture from the callus exhibits the usual growthcurve. The phenolic content follows a pattern different fromthat of growth, protein, and RNA content, and phenolics arerapidly synthesized as active growth ceases. In contrast tothe callus tissue, the suspension culture grows at a wide rangeof pH values and buffers the medium. At low temperatures in the light, potato discs produce greencallus with a chlorophyll content corresponding to that of thediscs from which they grew. The isolated callus tissue doesnot require kinetin and produces and excretes its own cytokinin(s).The amount synthesized varies over the growth cycle.     

Effect of microRNA-34a in cell cycle, differentiation, and apoptosis: a review

The tumor suppressor gene p53 was shown to directly regulate the expression of microRNA-34a (miR-34a). miR-34a regulates a plethora of target proteins, which are involved in cell cycle, apoptosis, differentiation, and cellular development.miR-34a resides in the region of chromosome 1p36.23, which is commonly deleted in many tumor types, while it results in the loss expression of miR-34a. The promoters of the miR-34a gene subject to inactivation by CpG methylation also induce the loss expression of miR-34a. Ectopic miR-34a expression induces apoptosis, cell cycle arrest, and differentiation or reduces migration. This review summarizes the progress regarding the role of miR-34a in cell cycle, differentiation, and apoptosis.     

Expression in yeast and purification of a membrane protein, SERCA1a, using a biotinylated acceptor domain

We have recently described the final steps leading to the crystallization of a mammalian membrane protein, the rabbit sarcoplasmic reticulum Ca2+-ATPase, after heterologous expression. Here, we detail the initial steps leading to this new purification method. A biotin acceptor domain was fused at the C-terminal part of Ca2+-ATPase and a thrombin site was inserted between both coding regions. The recombinant protein was expressed under the control of a galactose-inducible promoter in the yeast Saccharomyces cerevisiae. The biotinylation reaction of the protein was performed directly in vivo in yeast. After solubilization of the yeast light membrane fraction, the biotinylated protein was retained specifically using the strong biotin-avidin interaction. Finally, digestion by the protease thrombin allowed the separation of the Ca2+-ATPase from the biotinylated domain. At this step, Ca2+-ATPase is in a relatively purified form (about 40%). After a size-exclusion HPLC step, the purity of the protein is about 70%, and evaluation of the conformational changes during the catalytic cycle by monitoring the intrinsic fluorescence is demonstrated. The major advantage of this avidin procedure is the particularly good specific ATPase activity as compared with that of a purified His-tagged Ca2+-ATPase.     

Commensal relationship between a sheath-forming bacterium, Sphaerotilus natans, and a sheath-degrading bacterium, Paenibacillus sp

Paenibacillus sp. strain TB is capable of degrading the sheath prepared from a sheathed bacterium, Sphaerotilus natans. S. natans was able to grow alone on casamino acids but strain TB was not. Cocultivation of strain TB and S. natans was examined in a medium supplemented with casamino acids as a growth substrate. The growth of strain TB was observed when the sheath was supplied to the medium or in cocultivation with S. natans. The phospholipid amount reached a maximum after 24 h of cocultivation and subsequently kept almost the same level for 96 h. The sheath amount also reached a maximum after 24 h and then gradually declined. The cell concentration of strain TB increased throughout the cocultivation. By competitive PCR targeted for amplification of a part of 16S rDNA, the abundance ratio (S. natans/strain TB) of 6.7 was obtained at 72 h. Almost no growth of strain TB was detected in a coculture with a sheath-less mutant of S. natans. The evidence allows the conclusion that strain TB grew by utilizing the intact sheath in coculture with S. natans.     

Polyhydroxyalkanoates as a source of chemicals, polymers, and biofuels

Microbial polyhydroxyalkanoates (PHA) are a family of structurally diverse polyesters produced by many bacteria. Deleting key steps from the beta-oxidation cycle in Pseudomonas putida makes it possible to achieve precise substrate based design of PHA homopolymers, copolymers, and block polymers, allowing the study of structure-property relationship in a clear way. The PHA homopolymer synthesis also allows the microbial or chemical production of pure monomers of PHA in a convenient way without separating the mixed monomers. After used as bioplastics, PHA can be methyl esterified to become biofuels, which further extends the PHA application value. The microbial production of PHA with diverse structures is entering a new developing phase.     

Augmentation and evaluation of a parasitoid,Encarsia inaron,and a predator,Clitostethus arcuatus,for biological control of the pomegranate whitefly,Siphoninus phillyreae

The aim of this study was to evaluate the biological control potential of Encarsia inaron (Walker) (Hymenoptera: Aphelinidae) and a predator Clitostethus arcuatus (Rossi) (Coleoptera: Coccinellidae) against the pomegranate whitefly, Siphoninus phillyreae (Haliday) (Homoptera: Aleyrodidae) on pomegranate (Punica granatum L.) by mass rearing and augmentative releases of these two natural enemies during a long-term field study in Egypt. A study was conducted to evaluate the biological control potential of this pest by augmentation with a parasitoid, En. inaron, and a predator, C. arcuatus. Both species were mass reared and monthly releases were made in fields of pomegranate during each of 11 consecutive years (1996–2006). About 1,155,000 En. inaron and 990,000 C. arcuatus were released in fields in Assuit governorate in Egypt on pomegranate which was naturally infested by S. phillyreae. Populations of the natural enemies and parasitism were much higher in field plots where releases were made compared with where no releases were made. The maximum rate of parasitism reached 93% (88% by En. inaron) in the field treatment where releases were made, while parasitism peaked at 36% where no releases were made. The population of En. inaron was significantly correlated with the population of whitefly during the field season. Additional parasitism was by natural infestation with Eretmocerus parasiphonini Evans and Abd-Rabou (Hyneoptera: Aphelinidae). Among all years, the maximum number of C. arcuatus ranged from 13 to 44 beetles per 100 leaves for the treatment, and there were more predators in the release plot than in the control plot. These observations enhance understanding of the usefulness of these natural enemies after augmentation in the field.