<Emphasis Type="Italic">Brucella abortus ure2</Emphasis> region contains an acid-activated urea transporter and a nickel transport system

Background  

Urease is a virulence factor that plays a role in the resistance of Brucella to low pH conditions, both in vivo and in vitro. Brucella contains two separate urease gene clusters, ure1 and ure2. Although only ure1 codes for an active urease, ure2 is also transcribed, but its contribution to Brucella biology is unknown.     

Short‐term side effects of 0.2% alcohol‐free chlorhexidine mouthrinse in geriatric patients: a randomized,double‐blind,placebo‐controlled study

doi: 10.1111/j.1741‐2358.2012.00671.x Short‐term side effects of 0.2% alcohol‐free chlorhexidine mouthrinse in geriatric patients: a randomized, double‐blind, placebo‐controlled study Objective: To determine the effects of a 0.2% alcohol‐free chlorhexidine mouthwash applied twice a day during 30 days in patients over 65 years of age. Materials and methods: A randomized, double‐blind, placebo‐controlled study was made of 70 denture wearers over 65 years of age. The study subjects were randomly assigned to one of the two groups (chlorhexidine or placebo). The patients were instructed to complete a first whitening phase with a duration of 1 week, followed by a 30‐day treatment period. The following data were collected: Silness and Löe plaque index, gingival index, the number of colony‐forming units of Candida albicans at the start and end of treatment and the possible adverse effects of chlorhexidine. Results: Significant differences were observed in the evolution of the Silness and Löe plaque index and gingival index in the two groups, as well as in the number of colony‐forming units of C. albicans between the start and end of treatment. Conclusions: These results suggest that the clinical benefits of antiplaque, antigingivitis mouthrinses in both study groups.     

A new tropiduchid planthopper genus and species from China with descriptions of in copula genitalic structures (Hemiptera: Fulgoromorpha)

Abstract The new planthopper taxon, Garumnella bella gen.n. , sp.n. , from Xizang, China, is described and illustrated, including external morphology of adult and eggs and structures of the male and female genitalia. The new genus is compared with Garumna Melichar and Paragarumna Muir, resulting in Paragarumna ( syn.n. ) being placed as a junior synonym of Garumna, with two new combinations, i.e. Garumna pseudolepida (Muir) comb.n. and Garumna melichari Baker comb.rev. New locality records for Garumna species are given. The morphology of the genitalia and egg of a copulating pair of the new genus is investigated. The female has a ventrally sclerotized posterior vagina forming a torsion groove, an unusual long membranous anterior vagina and an enlarged common oviduct. During copulation both the aedeagus and the torsion groove appear tightly interlocked, which may help to maintain the copulatory position. The aedeagus is observed in the bursa copulatrix.     

基于GC-MS代谢组学技术委陵菜与星毛委陵菜的初生代谢比较研究

为明确药用植物委陵菜与其同属植物星毛委陵菜在不同基原之间的代谢差异，更有效的利用药用植物资源。基于气相色谱与质谱联用技术对两药用植物间的小分子初生代谢物进行非靶向代谢组学分析，利用主成分分析和偏最小二乘法分析，寻找可区分两物种的差异代谢物以及在初生代谢途径上的差异。结果：利用GC-MS在两植物中共检测到134个色谱峰，通过与数据库比对，共鉴定出43种初生代谢产物。PCA分析结果显示代谢物在委陵菜和星毛委陵菜间的分布有较大的差异；采用OPLS-DA筛选获得导致2物种区分的差异代谢物共33种，两物种在半乳糖代谢、淀粉和蔗糖代谢、氨酰生物合成、氨基糖和核苷酸糖代谢和果糖和甘露糖代谢途径有显著的差异。委陵菜和星毛委陵菜的初生代谢方面存在较大差异，虽然两植物来源于同科同属植物，但是星毛委陵菜不适合代替委陵菜作为药材使用。     

Lysozymes in insects: what role do they play in nitrogen metabolism?

Abstract. Lysozymes are widely distributed in many organisms as one of the components of defence mechanisms. In herbivores, when nitrogen is not contained in sufficient amounts in the diet, bacteria lysed by stomach lysozymes are used as sources of nitrogen. In ruminants, lysozymes function as digestive enzymes in the true stomach. A convergence of amino acid sequence has been shown between the stomach lysozymes of different ruminants, and similar lysozymes have recently been reported in the gut or salivary gland of insects. In this mini review, the enzymatic and ecological functions of lysozymes in insects, particularly in termites, are introduced, together with future studies that are needed in this field.     

A new extant respirometric assay to estimate intrinsic growth parameters applied to study plasmid metabolic burden

Start‐up phenomena in microbial biokinetic assays are not captured by the most commonly used growth‐related equations. In this study we propose a new respirometric experimental design to estimate intrinsic growth parameters that allow us to avoid these limitations without data omission, separate mathematical treatment, or wake‐up pulses prior to the analysis. Identifiability and sensitivity analysis were performed to confirm the robustness of the new approach for obtaining unique and accurate estimates of growth kinetic parameters. The new experimental design was applied to establish the metabolic burden caused by the carriage of a pWW0 TOL plasmid in the model organism Pseudomonas putida KT2440. The metabolic burden associated was manifested as a reduction in the yield and the specific growth rate of the host, with both plasmid maintenance and the over‐expression of recombinant proteins from the plasmid contributing equally to the overall effect. Biotechnol. Bioeng. 2010;105: 141–149. © 2009 Wiley Periodicals, Inc.     

Preparation of 2,3-seco-5 alpha-cholestane-2,3-diol and 4 alpha-methyl-2,3-seco-5 alpha-cholestane-2,3-diol and its reactions with o-nitrophenyl selenocyanate

The reaction of 2,3-seco-5 alpha-cholestane-2,3-diol and 4 alpha-methyl-2,3-seco-5 alpha-cholestane-2,3-diol with o-nitrophenyl selenocyanate was studied. The diols were synthesized from cholesterol.     

Current distribution and potential expansion of the harmful benthic dinoflagellate Ostreopsis cf. siamensis towards the warming waters of the Bay of Biscay,North-East Atlantic

In a future scenario of increasing temperatures in North-Atlantic waters, the risk associated with the expansion of the harmful, benthic dinoflagellate Ostreopsis cf. siamensis has to be evaluated and monitored. Microscopy observations and spatio-temporal surveys of environmental DNA (eDNA) were associated with Lagrangian particle dispersal simulations to: (i) establish the current colonization of the species in the Bay of Biscay, (ii) assess the spatial connectivity among sampling zones that explain this distribution, and (iii) identify the sentinel zones to monitor future expansion. Throughout a sampling campaign carried out in August to September 2018, microscope analysis showed that the species develops in the south-east of the bay where optimal temperatures foster blooms. Quantitative PCR analyses revealed its presence across almost the whole bay to the western English Channel. An eDNA time-series collected on plastic samplers showed that the species occurs in the bay from April to September. Due to the water circulation, colonization of the whole bay from the southern blooming zones is explained by inter-site connectivity. Key areas in the middle of the bay permit continuous dispersal connectivity towards the north. These key areas are proposed as sentinel zones to monitor O. cf. siamensis invasions towards the presumably warming water of the North-East Atlantic.     

Substances Isolated from Woody Cuttings of Salix atrocinerea and Their Growth Properties

A study of the cuttings of Salix atrocinerea Brot. was made by extraction with methanol, paper chromatography and Avena coleoptile straight growth test. In the acidic fraction, indole-3-acetic acid (IAA; about 15 μg per kg fresh weight) and p-hydroxybenzoic acid (PHB; about 850 μg per kg fresh weight) were isolated and identified. The growth activity of the different zones is explained by their content of these two compounds. The watersoluble residue, insoluble in ether, showed growth Stimulating activity, which probably is due to a bound auxin (IAA-sugar); alkaline breakdown of this aqueous residue, giving PHB, vanillic and p-coumaric acids, suggests the presence (in the cuttings of Salix atrocinerea) of glycosides with aglycones similar to rhamnacine and scutellareine.     

Multiple antibiotic susceptibility associated with inactivation of the prc gene.

A Tn5 insertion which led to increased susceptibility to multiple drugs, including tetracycline, chloramphenicol, nalidixic acid, erythromycin, spectinomycin, norfloxacin, and novobiocin, was identified in Escherichia coli. Cloning and sequence studies showed that the insertion was in the previously identified prc gene at min 40.4. The prc product is known to function as a protease linked to processing of penicillin-binding protein 3 and lambda repressor and when absent to allow some leakage of periplasmic constituents. Complementation studies with the prc gene on plasmids showed complete recovery of parental levels of susceptibility to all drugs except chloramphenicol, with which only partial reversion to wild-type levels was observed.