bluuebunny/crossref_metadata_2025 huggingface dataset:
ISO 9001:2000 implementation in the Greek food sector
Authors: Fotopoulos Christos V. , Psomas Evangelos L. , Vouzas Fotis K.
Published: February 2010

Purpose

The purpose of this paper is to examine perceptions of the implementation of the ISO 9001:2000 standard in the food sector in Greece.

Design/methodology/approach

Research was conducted in 97 Greek food companies certified to ISO 9001:2000, using the questionnaire method and aimed at examining the reasons for certification, the difficulties in implementing the standard, the benefits of certification and their relationships. Exploratory Factor Analysis and Multiple Linear Regression Analysis was applied to define the main constructs of reasons‐benefits‐difficulties and to explore their relationships.

Findings

Results showed that the major reasons for certification, unlike benefits, concern firstly the internal business environment and then the external one and no particular difficulties were observed during the standard implementation. Achieving internal (external) benefits is positively affected by the existence of internal (external) reasons and negatively affected by the difficulties to meet the standard's requirements.

Research limitations/implications

The present study is based on subjective data that refer to a short ISO 9001:2000 certification period. A more thorough research on food companies that have been certified for a long period using data coming from their internal environment, such as executives, managers, employees, would offer more information about ISO 9001:2000 and would reveal its impact on business performance.

Practical implications

The results of the study will be of great use to food companies that have not been certified yet, particularly in light of the new challenge they face with the ISO 22000 standard.

Originality value

The present study is exclusively focused on companies in the Greek food sector in order to draw information about the revised ISO 9001:2000 standard.
Integrated lean TQM model for global sustainability and competitiveness
Authors: Ho Samuel K.M.
Published: February 2010

Purpose

The purpose of this paper is to explore an integrated total quality management (TQM) model for global sustainability.

Design/methodology/approach

It has been well‐recognised that Japanese firms compete in quality, cost and speed of delivery. Over the last century, the Japanese have formalised the technique and call it “5S” Practice. Through his research in Japan under the “Oshikawa Fellowship” of the Asian Productivity Organisation in 1988, the author has re‐defined the name as “the 5‐S” and developed the world's first 5‐S Audit Checklist. Recently, in the wake of the soaring oil prices, the author developed another Checklist on Lean 5‐S, aiming at minimising wastage of all kinds. Thus, the author adds another dimension to the Japanese competitiveness trio above – environment. Since 1993, the author has used the proprietary 5‐S Checklist for training and consultancy in no less than ten countries with over 100,000 persons from around 8,000 organisations worldwide. On the other hand, HKSAR takes the lead in the global oil energy consumption/GPD. The experience is shared in this paper.

Findings

On entering into year 2008, the price of oil soared to US$148/barrel, and kept rising. This calls for the pressing need for lean, the most important word for any organisation in the contemporary world. By now, the oil crisis seems to be over. Unfortunately, it has ignited the financial tsunami, a much bigger problem than the oil crisis, which we can live with. The lean management model proposed in this paper has shown some evidence to help organisations overcome the damages caused by the financial tsunami.

Research limitations/implications

As the Integrated Lean TQM Model has only been tested in HKSAR, China and Japan, interested academics and related parties are invited to join in to validate this model for the global sustainability and competitiveness.

Originality/value

The greatest contribution to the field of TQM in this paper are the two checklists created, each of them with 50 checkpoints, and tested by the author. When used properly, these two checklists are the corner stones for competitiveness and global sustainability in resources management.
The applicability of quality management systems and models to higher education
Authors: Mehralizadeh Yadollah , Safaeemoghaddam Massoud
Published: February 2010

Purpose

The main purpose of this paper is study to what extent the idea of a total quality management (TQM) system (Deming, ISO, Baldrige, and EFQM) which is borrowed from business is applicable in a higher education institution.

Design/methodology/approach

A meta‐evaluation methodology is used which emphasises Røvik's seven theoretical assumptions on how management ideas are spread in a given sector.

Findings

The findings of this paper reveal that that in many cases the current evidence of application of TQM is not compatible with the assumed criteria of the Røvik model. The quality systems are not often socially acceptable, they do not follow a clear philosophy and theory, do not show the productivity of institutions, are less progressive, have low harmonies, unrealistically publicized but in terms of individualized aspects there are some supportive successful case applied in non‐academic higher education.

Originality/value

The value and new message of this paper is its investigation of the fitness of TQM from a new perspective based on meta‐analysis.
A study into the effectiveness of quality management training
Authors: Clegg Ben , Rees Chris , Titchen Mike
Published: February 2010

Purpose

The purpose of this paper is to investigate the effectiveness of quality management training by reviewing commonly used critical success factors and tools rather than the overall methodological approach.

Design/methodology/approach

The methodology used a web‐based questionnaire. It consisted of 238 questions covering 77 tools and 30 critical success factors selected from leading academic and practitioner sources. The survey had 79 usable responses and the data were analysed using relevant statistical quality management tools. The results were validated in a series of structured workshops with quality management experts.

Findings

Findings show that in general most of the critical success factor statements for quality management are agreed with, although not all are implemented well. The findings also show that many quality tools are not known or understood well; and that training has an important role in raising their awareness and making sure they are used correctly.

Research limitations/implications

Generalisations are limited by the UK‐centric nature of the sample.

Practical implications

The practical implications are discussed for organisations implementing quality management initiatives, training organisations revising their quality management syllabi and academic institutions teaching quality management.

Originality/value

Most recent surveys have been aimed at methodological levels (i.e. “lean”, “Six Sigma”, “total quality management” etc.); this research proposes that this has limited value as many of the tools and critical success factors are common to most of the methodologies. Therefore, quite uniquely, this research focuses on the tools and critical success factors. Additionally, other recent comparable surveys have been less comprehensive and not focused on training issues.
A theoretical and empirical research on the mediating effect of internal entrepreneurial environment
Authors: Li Qianwen , Zhang Ziyuan
Published: February 2010

Purpose

The purpose of this paper is to explore the mediating effect of internal entrepreneurial environment (IEE) between entrepreneurial orientation (EO) and organizational performance.

Design/methodology/approach

The research is conducted using an original data set of 185 in China. The mediator measurement steps recommended by Baron and Kenny to test the mediating effects are applied.

Findings

The proposition that EO can lead to the improvement of organizational performance is only partially confirmed in this paper; IEE is the mediating variable between innovation‐proactive and organizational performance, but the dimension of risk‐taking is not verified.

Research limitations/implications

As far as the IEE measurement scale is concerned, its simplicity is achieved at the cost of accuracy. Future research may adopt more complex scale design to further verify the relationship among the different sub‐dimensions of IEE, as well as the correlation and causality between those dimensions and organizational performance.

Originality/value

The complex relationship between EO and organizational performance requires further study of the contingency and construction of third‐party variables. This research confirms that building IEE is an important path for transforming EO into organizational performance.
Humanity and trendiness
Authors: He Jiaxun
Published: February 2010

Purpose

The purpose of this paper is to reveal the key dimensions reflecting the differences between Chinese and foreign brands, evaluate different consumption generations, and provide evidence for studying differences and similarities of brand personality dimensions from a cross‐cultural perspective.

Design/methodology/approach

Using a questionnaire survey among a large sample of people in three cities of China, brand personality of Chinese and foreign brands was measured by an indigenous scale. Principal component analysis and nonparametric tests were used to analyze the data.

Findings

Two key dimensions of humanity and trendiness were found and compared with Aaker's scale. Differences in dimensions of brand personality were also identified through comparing foreign brands with local brands as well as consumption by the younger and older generations. In conclusion, China's local brands show a higher level of humanity but a lower level of trendiness. The young generation has significantly higher demands for trendiness than the old generation.

Research limitations/implications

In order to test the robustness of the conclusions of this paper, a more popular interval variable type is needed for further study. In addition, the conclusions drawn from this may not be completely suitable for other industries or categories.

Practical implications

The results have some important implications for building the image of China's local brands, especially time‐honored brands. The key approach is to create a trendiness association while keeping points of difference association on humanity.

Originality/value

Previous research has demonstrated cross‐cultural differences and similarities in the evaluations of brand personality, but there are no studies in the context of the Chinese market. The findings of this paper support the argument that the key dimensions of brand personality exist across different cultures.
Global entrepreneurship and supply chain management: a Chinese exemplar
Authors: Wu Lifang , Park Daewoo , Chinta Ravi , Cunningham Margaret
Published: February 2010

Purpose

Global entrepreneurship study is primarily concerned with why, when, and how entrepreneurial opportunities are discovered and exploited in the global market. The purpose of this paper is to present a framework for pursuing global entrepreneurship where supply chain management (SCM) can often serve as a platform for resource acquisition, market development, and risk mitigation.

Design/methodology/approach

This paper presents a case study to show how SCM is utilized by entrepreneurs in China for developing two formats of entrepreneurship: domestic private companies through horizontal supply chain clustering and vertical (forward and/or backward) supply chain extensions. In particular, the paper explores firm‐level behavior in supply clusters to discern patterns at the collective level of supply clusters.

Findings

Entrepreneurs rely on their existing supply chain networks to pursue new venturing opportunities. Two types of supply chain expansions (horizontal supply chain clustering and vertical supply chain extensions) are found in China. Competitive rivalry in this paper of supply clusters is found to demonstrate “co‐opetition” (collaboration amongst competitors).

Originality/value

This paper's theoretical framework offers unique perspectives towards global entrepreneurship, and is empirically supported by numerous real business examples. The paper integrates SCM with international entrepreneurship and identifies two distinct patterns that are evident in China. In particular, the paper describes the specific contexts in which each of the two patterns is successful. These patterns provide valuable guidance for future Chinese entrepreneurs interested in globalization. The paper is a harbinger to future research on collective behavior of competitors in supply clusters. This could potentially redefine competitive rivalry (in Porter's 5‐forces) in more cooperative terms.
Systematic review: impact of constipation on quality of life in adults and children
Authors: BELSEY J. , GREENFIELD S. , CANDY D. , GERAINT M.
Published: February 2010

Aliment Pharmacol Ther 31, 938–949

Background  Comparison of quality of life (QoL) across disease areas requires the use of appropriate tools. Although many studies have investigated QoL in constipation, most used disease‐specific tools that are inappropriate for cross‐comparisons.

Aims  To identify studies of QoL in constipation and to compare these results with other chronic conditions.

Methods  A comprehensive literature search identified studies in constipation that used a generic QoL tool. Results were statistically pooled where possible and compared with published results using the same tools in other chronic conditions.

Results  A total of 13 qualifying studies were identified, 10 in adults and three in children. Results from eight studies using the SF‐36/12 tools were pooled; the remaining five were narratively reported. Mental and physical components of QoL scores were consistently impaired in both adult and child populations, with the greatest impact being seen in secondary care studies. Mental health effects predominated over physical domains. The magnitude of impact was comparable with that seen in patients with allergies, musculoskeletal conditions and inflammatory bowel disease.

Conclusions  The impact of constipation on QoL is significant and comparable with other common chronic conditions. Improving management may prove to be an effective way of improving QoL for a substantial number of patients.
Clinical trial: clarithromycin vs. levofloxacin in first‐line triple and sequential regimens for Helicobacter pylori eradication
Authors: MOLINA‐INFANTE J. , PEREZ‐GALLARDO B. , FERNANDEZ‐BERMEJO M. , HERNANDEZ‐ALONSO M. , VINAGRE G. , DUEÑAS C. , MATEOS‐RODRIGUEZ J. M. , GONZALEZ‐GARCIA G. , ABADIA E. G. , GISBERT J. P.
Published: February 2010

Aliment Pharmacol Ther 31, 1077–1084

Background  Helicobacter pylori eradication rates with standard triple therapy have declined to unacceptable levels.

Aim  To compare clarithromycin and levofloxacin in triple and sequential first‐line regimens.

Methods  A total of 460 patients were randomized into four 10‐day therapeutic schemes (115 patients per group): (i) standard OCA, omeprazole, clarithromycin and amoxicillin; (ii) triple OLA, omeprazole, levofloxacin and amoxicillin; (iii) sequential OACM, omeprazole plus amoxicillin for 5 days, followed by omeprazole plus clarithromycin plus metronidazole for 5 days; and (iv) modified sequential OALM, using levofloxacin instead of clarithromycin. Eradication was confirmed by 13C‐urea breath test. Adverse effects and compliance were assessed by a questionnaire.

Results  Per protocol cure rates were: OCA (66%; 95% CI: 57–74%), OLA (82.6%; 75–89%), OACM (80.8%; 73–88%) and OALM (85.2%; 78–91%). Intention‐to‐treat cure rates were: OCA (64%; 55–73%), OLA (80.8%; 73–88%), OACM (76.5%; 69–85%) and OALM (82.5%; 75–89%). Eradication rates were lower with OCA than with all the other regimens (P < 0.05). No differences in compliance or adverse effects were demonstrated among treatments.

Conclusions  Levofloxacin‐based and sequential therapy are superior to standard triple scheme as first‐line regimens in a setting with high clarithromycin resistance. However, all of these therapies still have a 20% failure rate.
Anther and stigma morphology in mirror‐image flowers of Chamaecrista chamaecristoides (Fabaceae): implications for buzz pollination
Authors: Arceo‐Gómez G. , Martínez M. L. , Parra‐Tabla V. , García‐Franco J. G.
Published: February 2010

Enantiostyly (mirror‐image flowers) is usually associated with buzz pollination. In buzz‐pollinated flowers, pollen is released through terminal pores after bees vibrate the stamens. Several studies have evaluated the function of ‘buzzing’ in pollen release, but less attention has been paid to the effect of buzzing on pollen capture and deposition on stigmas. Evaluating the mechanism of pollen dispersion in buzz‐pollinated flowers is important because it may affect mating patterns and reproductive success. In this study, we analysed the morphology of sexual organs (anther and stigma) using electron microscopy, and determined the relationship between sexual organ structure and pollen capture function through experimental manipulations of buzz‐pollinated flowers of Chamaecrista chamaecristoides, as well as vibration frequencies on floral visitors. Pollen release occurs through two terminal pores at the tip of the stamens. However, unlike most angiosperms that have their stigmatic surface exposed, C. chamaecristoides presents a stigmatic surface inside a cavity covered by trichomes. Experimental manipulations showed that effective fertilisation is only achieved when the style is vibrated, suggesting that buzzing is not only important for pollen release but also for pollen capture and deposition on the stigma. This result, in addition to vibration frequency analysis, suggests that although all floral visitors buzz flowers only those that buzz at higher frequencies achieve effective fertilisation. The anatomical features of sexual organs in flowers of C. chamaecristoides demonstrate that this species possesses a highly specialised, elaborate morphology, with both genders selected for traits that promote buzz pollination.
Lenalidomide and dexamethasone for the treatment of refractory/relapsed multiple myeloma: dosing of lenalidomide according to renal function and effect on renal impairment
Authors: Dimopoulos Meletios A. , Christoulas Dimitrios , Roussou Maria , Kastritis Efstathios , Migkou Magdalini , Gavriatopoulou Maria , Matsouka Charis , Mparmparoussi Despoina , Psimenou Erasmia , Grapsa Irini , Efstathiou Eleni , Terpos Evangelos
Published: February 2010

Objectives:  Lenalidomide and dexamethasone (LenDex) is an active regimen for relapsed/refractory multiple myeloma (MM). However, there is limited data for the effect of LenDex on renal impairment (RI) and on renal reversibility.

Patients & Methods:  Fifty consecutive patients with relapsed/refractory MM received LenDex in 28‐d cycles. Median lines of previous therapies were 2 (range: 1–6). Lenalidomide was administered on days 1–21 according to creatinine clearance (CrCl), while dexamethasone was given at a dose of 40 mg on days 1–4 and 15–18 for the first four cycles and only on days 1–4 thereafter.

Results:  Twelve patients (24%) had RI at baseline, defined as CrCl < 50 mL/min. Most patients were pretreated with either thalidomide or bortezomib and > 50% of them were refractory to both drugs. At least partial response was documented in 60.5% and 58% of patients with and without RI. Median progression‐free survival (PFS) and overall survival (OS) for all patients was 9 and 16 months, respectively. RI was not associated with an inferior PFS or OS. There were no differences in the incidence of adverse events among patients with and without RI. Three of 12 patients with RI (25%) achieved complete renal response and two (16%) achieved minor renal response with LenDex.

Conclusions:  We conclude that LenDex is an active treatment even in heavily pretreated MM. With dosing of lenalidomide according to renal function, LenDex can be administered to patients with RI (who may not have other treatment options) without excessive toxicity. Furthermore, LenDex may improve the renal function in approximately 40% of patients with RI.
Caffeine and theophylline block insulin‐stimulated glucose uptake and PKB phosphorylation in rat skeletal muscles
Authors: Kolnes A. J. , Ingvaldsen A. , Bolling A. , Stuenæs J. T. , Kreft M. , Zorec R. , Shepherd P. R. , Jensen J.
Published: February 2010

Aim: Caffeine and theophylline inhibit phosphatidylinositol 3‐kinase (PI3‐kinase) activity and insulin‐stimulated protein kinase B (PKB) phosphorylation. Insulin‐stimulated glucose uptake involves PI3‐kinase/PKB, and the aim of the present study was to test the hypothesis that caffeine and theophylline inhibit insulin‐stimulated glucose uptake in skeletal muscles.

Methods: Rat epitrochlearis muscles and soleus strips were incubated with insulin and different concentrations of caffeine and theophylline for measurement of glucose uptake, force development and PKB phosphorylation. The effect of caffeine was also investigated in muscles stimulated electrically.

Results: Caffeine and theophylline completely blocked insulin‐stimulated glucose uptake in both soleus and epitrochlearis muscles at 10 mm. Furthermore, insulin‐stimulated PKB Ser473and Thr308and GSK‐3β Ser9phosphorylation were blocked by caffeine and theophylline. Caffeine reduced and theophylline blocked insulin‐stimulated glycogen synthase activation. Caffeine stimulates Ca2+release and force development increased rapidly to 10–20% of maximal tetanic contraction. Dantrolene (25 μm), a well‐known inhibitor of Ca2+‐release, prevented caffeine‐induced force development, but caffeine inhibited insulin‐stimulated glucose uptake in the presence of dantrolene. Contraction, like insulin, stimulates glucose uptake via translocation of glucose transporter‐4 (GLUT4). Caffeine and theophylline reduced contraction‐stimulated glucose uptake by about 50%, whereas contraction‐stimulated glycogen breakdown was normal.

Conclusion: Caffeine and theophylline block insulin‐stimulated glucose uptake independently of Ca2+release, and the likely mechanism is via blockade of insulin‐stimulated PI3‐kinase/PKB activation. Caffeine and theophylline also reduced contraction‐stimulated glucose uptake, which occurs independently of PI3‐kinase/PKB, and we hypothesize that caffeine and theophylline also inhibit glucose uptake in skeletal muscles via an additional and hitherto unknown molecule involved in GLUT4 translocation.
Surface Display of Metal Fixation Motifs of Bacterial P1-Type ATPases Specifically Promotes Biosorption of Pb
2+
by
Saccharomyces cerevisiae
Authors: Kotrba Pavel , Ruml Tomas
Published: February 2010

Biosorption of metal ions may take place by different passive metal-sequestering processes such as ion exchange, complexation, physical entrapment, and inorganic microprecipitation or by a combination of these. To improve the biosorption capacity of the potential yeast biosorbent, short metal-binding NP peptides (harboring the CXXEE metal fixation motif of the bacterial Pb
2+
-transporting P1-type ATPases) were efficiently displayed and covalently anchored to the cell wall of
Saccharomyces cerevisiae
. These were fusions to the carboxyl-terminal part of the sexual adhesion glycoprotein α-agglutinin (AGα1Cp). Compared to yeast cells displaying the anchoring domain only, those having a surface display of NP peptides multiplied their Pb
2+
biosorption capacity from solutions containing a 75 to 300 μM concentration of the metal ion up to 5-fold. The S-type Pb
2+
biosorption isotherms, plus the presence of electron-dense deposits (with an average size of 80 by 240 nm, observed by transmission electron microscopy) strongly suggested that the improved biosorption potential of NP-displaying cells is due to the onset of microprecipitation of Pb species on the modified cell wall. The power of an improved capacity for Pb biosorption was also retained by the isolated cell walls containing NP peptides. Their Pb
2+
biosorption property was insensitive to the presence of a 3-fold molar excess of either Cd
2+
or Zn
2+
. These results suggest that the biosorption mechanism can be specifically upgraded with microprecipitation by the engineering of the biosorbent with an eligible metal-binding peptide.
Autonomous Growth of Isolated Single
Listeria monocytogenes
and
Salmonella enterica
Serovar Typhimurium Cells in the Absence of Growth Factors and Intercellular Contact
Authors: Roeder Barbara , Wagner Martin , Rossmanith Peter
Published: February 2010

The aim of this study was to observe growth of isolated single bacterial cells in the absence of growth factors and intercellular contact. In order to exclude stochastic uncertainties induced by dilution series, a new micromanipulation method was developed to ensure explicit results under visual control. This was performed with particular care for production of single prokaryotic cells and subsequent investigation of their autonomous growth. Over 450 single isolated
Listeria monocytogenes
and
Salmonella enterica
subsp.
enterica
serovar Typhimurium cells in lag, log, and stationary growth phases were investigated by this method, which included thoroughly washing the cells. The proportion of living cells within the initial cultures was compared to the proportion of positive samples after enrichment of the separated single cells. This resulted in
P
values of ≥0.05 using the chi-square test for statistical analysis, indicating no significant difference, and clearly demonstrates reproduction of isolated single bacterial cells without the need for growth factors or intercellular contact. Ease of handling of the apparatus and good performance of the cleaning procedures were achieved, as was validation of the method, demonstrating its suitability for routine laboratory use.
Use of Ichip for High-Throughput
In Situ
Cultivation of “Uncultivable” Microbial Species
Authors: Nichols D. , Cahoon N. , Trakhtenberg E. M. , Pham L. , Mehta A. , Belanger A. , Kanigan T. , Lewis K. , Epstein S. S.
Published: February 2010

One of the oldest unresolved microbiological phenomena is why only a small fraction of the diverse microbiological population grows on artificial media. The “uncultivable” microbial majority arguably represents our planet's largest unexplored pool of biological and chemical novelty. Previously we showed that species from this pool could be grown inside diffusion chambers incubated
in situ
, likely because diffusion provides microorganisms with their naturally occurring growth factors. Here we utilize this approach and develop a novel high-throughput platform for parallel cultivation and isolation of previously uncultivated microbial species from a variety of environments. We have designed and tested an isolation chip (ichip) composed of several hundred miniature diffusion chambers, each inoculated with a single environmental cell. We show that microbial recovery in the ichip exceeds manyfold that afforded by standard cultivation, and the grown species are of significant phylogenetic novelty. The new method allows access to a large and diverse array of previously inaccessible microorganisms and is well suited for both fundamental and applied research.
Activation of the Ustilagic Acid Biosynthesis Gene Cluster in
Ustilago maydis
by the C
2
H
2
Zinc Finger Transcription Factor Rua1
Authors: Teichmann Beate , Liu Lidan , Schink Kay Oliver , Bölker Michael
Published: February 2010

The phytopathogenic basidiomycetous fungus
Ustilago maydis
secretes, under conditions of nitrogen starvation, large amounts of the biosurfactant ustilagic acid (UA). This secreted cellobiose glycolipid is toxic for many microorganisms and confers biocontrol activity to
U. maydis
. Recently, a large gene cluster that is responsible for UA biosynthesis was identified. Here, we show that expression of all cluster genes depends on Rua1, a nuclear protein of the C
2
H
2
zinc finger family, whose gene is located within the gene cluster. While deletion of
rua1
results in complete loss of UA production, overexpression of
rua1
promotes increased UA synthesis even in the presence of a good nitrogen source. Bioinformatic analysis allowed us to identify a conserved sequence element that is present in the promoters of all structural genes involved in UA biosynthesis. Deletion analysis of several promoters within the cluster revealed that this DNA element serves as an upstream activating sequence (UAS) and mediates Rua1-dependent expression. We used the yeast one-hybrid system to demonstrate specific recognition of this DNA element by Rua1. Introduction of nucleotide exchanges into the consensus sequence interfered with Rua1-dependent activation, suggesting that this sequence element acts as a direct binding site for Rua1.
Promotion of Efficient Saccharification of Crystalline Cellulose by
Aspergillus fumigatus
Swo1
Authors: Chen Xin-ai , Ishida Nobuhiro , Todaka Nemuri , Nakamura Risa , Maruyama Jun-ichi , Takahashi Haruo , Kitamoto Katsuhiko
Published: February 2010

Swollenin is a protein from
Trichoderma reesei
that has a unique activity for disrupting cellulosic materials, and it has sequence similarity to expansins, plant cell wall proteins that have a loosening effect that leads to cell wall enlargement. In this study we cloned a gene encoding a swollenin-like protein, Swo1, from the filamentous fungus
Aspergillus fumigatus
, and designated the gene
Afswo1
. AfSwo1 has a bimodular structure composed of a carbohydrate-binding module family 1 (CBM1) domain and a plant expansin-like domain. AfSwo1 was produced using
Aspergillus oryzae
for heterologous expression and was easily isolated by cellulose-affinity chromatography. AfSwo1 exhibited weak endoglucanase activity toward carboxymethyl cellulose (CMC) and bound not only to crystalline cellulose Avicel but also to chitin, while showing no detectable affinity to xylan. Treatment by AfSwo1 caused disruption of Avicel into smaller particles without any detectable reducing sugar. Furthermore, simultaneous incubation of AfSwo1 with a cellulase mixture facilitated saccharification of Avicel. Our results provide a novel approach for efficient bioconversion of crystalline cellulose into glucose by use of the cellulose-disrupting protein AfSwo1.
Identification of Multiresistant
Salmonella
Isolates Capable of Subsisting on Antibiotics
Authors: Barnhill Alison E. , Weeks Katherine E. , Xiong Nalee , Day Tim A. , Carlson Steve A.
Published: February 2010

This study assessed the ability of
Salmonella
(572 isolates) to subsist on 12 different antibiotics. The majority (11/12) of the antibiotics enabled subsistence for at least 1 of 140 isolates. Furthermore, 40 isolates were able to subsist on more than one antibiotic. Antibiotic resistance and antibiotic subsistence do not appear to be equivalent.
Bacterial and Protozoal Communities and Fatty Acid Profile in the Rumen of Sheep Fed a Diet Containing Added Tannins
Authors: Vasta Valentina , Yáñez-Ruiz David R. , Mele Marcello , Serra Andrea , Luciano Giuseppe , Lanza Massimiliano , Biondi Luisa , Priolo Alessandro
Published: February 2010

This study evaluated the effects of tannins on ruminal biohydrogenation (BH) due to shifts in the ruminal microbial environment in sheep. Thirteen lambs (45 days of age) were assigned to two dietary treatments: seven lambs were fed a barley-based concentrate (control group) while the other six lambs received the same concentrate with supplemental quebracho tannins (9.57% of dry matter). At 122 days of age, the lambs were slaughtered, and the ruminal contents were subjected to fatty acid analysis and sampled to quantify populations of
Butyrivibrio fibrisolvens
, which converts C
18:2
c
9-
c
12 (linoleic acid [LA]) to C
18:2
c
9-
t
11 (rumenic acid [RA]) and then RA to C
18:1
t
11 (vaccenic acid [VA]); we also sampled for
Butyrivibrio proteoclasticus
, which converts VA to C
18:0
(stearic acid [SA]). Tannins increased (
P
< 0.005) VA in the rumen compared to the tannin-free diet. The concentration of SA was not affected by tannins. The SA/VA ratio was lower (
P
< 0.005) for the tannin-fed lambs than for the controls, suggesting that the last step of the BH process was inhibited by tannins. The
B. proteoclasticus
population was lower (−30.6%;
P
< 0.1), and
B. fibrisolvens
and protozoan populations were higher (+107% and +56.1%, respectively;
P
< 0.05) in the rumen of lambs fed the tannin-supplemented diet than in controls. These results suggest that quebracho tannins altered BH by changing ruminal microbial populations.
Role of GlnR in Acid-Mediated Repression of Genes Encoding Proteins Involved in Glutamine and Glutamate Metabolism inStreptococcus mutans
Authors: Chen Pei-Min , Chen Yi-Ywan M. , Yu Sung-Liang , Sher Singh , Lai Chern-Hsiung , Chia Jean-San
Published: February 2010

The acid tolerance response (ATR) is one of the major virulence traits ofStreptococcus mutans. In this study, the role of GlnR in acid-mediated gene repression that affects the adaptive ATR inS. mutanswas investigated. Using a whole-genome microarray andin silicoanalyses, we demonstrated that GlnR and the GlnR box (ATGTNAN7TNACAT) were involved in the transcriptional repression of clusters of genes encoding proteins involved in glutamine and glutamate metabolism under acidic challenge. Reverse transcription-PCR (RT-PCR) analysis revealed that the coordinated regulation of the GlnR regulon occurred 5 min after acid treatment and that prolonged acid exposure (30 min) resulted in further reduction in expression. A lower level but consistent reduction in response to acidic pH was also observed in chemostat-grown cells, confirming the negative regulation of GlnR. The repression by GlnR through the GlnR box in response to acidic pH was further confirmed in thecitBZCoperon, containing genes encoding the first three enzymes in the glutamine/glutamate biosynthesis pathway. The survival rate of the GlnR-deficient mutant at pH 2.8 was more than 10-fold lower than that in the wild-type strain 45 min after acid treatment, suggesting that the GlnR regulon participates inS. mutansATR. It is hypothesized that downregulation of the synthesis of the amino acid precursors in response to acid challenge would promote citrate metabolism to pyruvate, with the consumption of H+and potential ATP synthesis. Such regulation will ensure an optimal acid adaption inS. mutans.
Increased Crystalline Cellulose Activity via Combinations of Amino Acid Changes in the Family 9 Catalytic Domain and Family 3c Cellulose Binding Module of
Thermobifida fusca
Cel9A
Authors: Li Yongchao , Irwin Diana C. , Wilson David B.
Published: February 2010

Amino acid modifications of the
Thermobifida fusca
Cel9A-68 catalytic domain or carbohydrate binding module 3c (CBM3c) were combined to create enzymes with changed amino acids in both domains. Bacterial crystalline cellulose (BC) and swollen cellulose (SWC) assays of the expressed and purified enzymes showed that three combinations resulted in 150% and 200% increased activity, respectively, and also increased synergistic activity with other cellulases. Several other combinations resulted in drastically lowered activity, giving insight into the need for a balance between the binding in the catalytic cleft on either side of the cleavage site, as well as coordination between binding affinity for the catalytic domain and CBM3c. The same combinations of amino acid variants in the whole enzyme, Cel9A-90, did not increase BC or SWC activity but did have higher filter paper (FP) activity at 12% digestion.
AiiM, a Novel Class of
N
-Acylhomoserine Lactonase from the Leaf-Associated Bacterium
Microbacterium testaceum
Authors: Wang Wen-Zhao , Morohoshi Tomohiro , Ikenoya Masashi , Someya Nobutaka , Ikeda Tsukasa
Published: February 2010

N
-Acylhomoserine lactones (AHLs) are used as quorum-sensing signal molecules by many Gram-negative bacteria. We have reported that
Microbacterium testaceum
StLB037, which was isolated from the leaf surface of potato, has AHL-degrading activity. In this study, we cloned the
aiiM
gene from the genomic library of StLB037, which has AHL-degrading activity and shows high homology with the α/β hydrolase fold family from
Actinobacteria
. Purified AiiM as a maltose binding fusion protein showed high degrading activity of AHLs with both short- and long-chain AHLs with or without substitution at carbon 3. High-performance liquid chromatography analysis revealed that AiiM works as an AHL lactonase that catalyzes AHL ring opening by hydrolyzing lactones. In addition, expression of AiiM in the plant pathogen
Pectobacterium carotovorum
subsp.
carotovorum
reduced pectinase activity markedly and attenuated soft rot symptoms on potato slices. In conclusion, this study indicated that AiiM might be effective in quenching quorum sensing of
P. carotovorum
subsp.
carotovorum
.
Thiosulfate-Dependent Chemolithoautotrophic Growth of
Bradyrhizobium japonicum
Authors: Masuda Sachiko , Eda Shima , Ikeda Seishi , Mitsui Hisayuki , Minamisawa Kiwamu
Published: February 2010

Thiosulfate-oxidizing
sox
gene homologues were found at four loci (I, II, III, and IV) on the genome of
Bradyrhizobium japonicum
USDA110, a symbiotic nitrogen-fixing bacterium in soil. In fact,
B. japonicum
USDA110 can oxidize thiosulfate and grow under a chemolithotrophic condition. The deletion mutation of the
soxY
1
gene at the
sox
locus I, homologous to the sulfur-oxidizing (Sox) system in
Alphaproteobacteria
, left
B. japonicum
unable to oxidize thiosulfate and grow under chemolithotrophic conditions, whereas the deletion mutation of the
soxY
2
gene at
sox
locus II, homologous to the Sox system in green sulfur bacteria, produced phenotypes similar to those of wild-type USDA110. Thiosulfate-dependent O
2
respiration was observed only in USDA110 and the
soxY
2
mutant and not in the
soxY
1
mutant. In the cells, 1 mol of thiosulfate was stoichiometrically converted to approximately 2 mol of sulfate and consumed approximately 2 mol of O
2
.
B. japonicum
USDA110 showed
14
CO
2
fixation under chemolithotrophic growth conditions. The CO
2
fixation of resting cells was significantly dependent on thiosulfate addition. These results show that USDA110 is able to grow chemolithoautotrophically using thiosulfate as an electron donor, oxygen as an electron acceptor, and carbon dioxide as a carbon source, which likely depends on
sox
locus I including the
soxY
1
gene on USDA110 genome. Thiosulfate oxidation capability is frequently found in members of the
Bradyrhizobiaceae
, which phylogenetic analysis showed to be associated with the presence of
sox
locus I homologues, including the
soxY
1
gene of
B. japonicum
USDA110.
Cre-
lox
-Based Method for Generation of Large Deletions within the Genomic Magnetosome Island of
Magnetospirillum gryphiswaldense
Authors: Ullrich Susanne , Schüler Dirk
Published: February 2010

Magnetosome biomineralization and magnetotaxis in magnetotactic bacteria are controlled by numerous, mostly unknown gene functions that are predominantly encoded by several operons located within the genomic magnetosome island (MAI). Genetic analysis of magnetotactic bacteria has remained difficult and requires the development of novel tools. We established a Cre-
lox
-based deletion method which allows the excision of large genomic fragments in
Magnetospirillum gryphiswaldense
. Two conjugative suicide plasmids harboring
lox
sites that flanked the target region were subsequently inserted into the chromosome by homologous recombination, requiring only one single-crossover event, respectively, and resulting in a double cointegrate. Excision of the targeted chromosomal segment that included the inserted plasmids and their resistance markers was induced by
trans
expression of Cre recombinase, which leaves behind a scar of only a single
loxP
site. The Cre helper plasmid was then cured from the deletant strain by relief of antibiotic selection. We have used this method for the deletion of 16.3-kb, 61-kb, and 67.3-kb fragments from the genomic MAI, either in a single round or in subsequent rounds of deletion, covering a region of approximately 87 kb that comprises the
mamAB
,
mms6
, and
mamGFDC
operons. As expected, all mutants were Mag
−
and some were Mot
−
; otherwise, they showed normal growth patterns, which indicates that the deleted region is not essential for viability in the laboratory. The method will facilitate future functional analysis of magnetosome genes and also can be utilized for large-scale genome engineering in magnetotactic bacteria.
Effects of Polyphosphate Additives on
Campylobacter
Survival in Processed Chicken Exudates
Authors: Gunther Nereus W.
Published: February 2010

Campylobacter
spp. are responsible for a large number of the bacterial food poisoning cases worldwide. Despite being sensitive to oxygen and nutritionally fastidious,
Campylobacter
spp. are able to survive in food processing environments and reach consumers in sufficient numbers to cause disease. To investigate
Campylobacter
persistence on processed chicken, exudates from chickens produced for consumer sale were collected and sterilized. Two types of exudates from chicken products were collected: enhanced, where a marinade was added to the chickens during processing, and nonenhanced, where no additives were added during processing. Exudates from enhanced chicken products examined in this study contained a mixture of polyphosphates. Exudate samples were inoculated with
Campylobacter jejuni
or
Campylobacter coli
strains and incubated under a range of environmental conditions, and viable bacteria present in the resultant cultures were enumerated. When incubated at 42°C in a microaerobic environment, exudates from enhanced chicken products resulted in increased survival of
C. jejuni
and
C. coli
compared with that in nonenhanced exudates in the range of <1 to >4 log CFU/ml. Under more relevant food storage conditions (4°C and normal atmosphere), the exudates from enhanced chicken products also demonstrated improved
Campylobacter
survival compared with that in nonenhanced exudates. Polyphosphates present in the enhanced exudates were determined to be largely responsible for the improved survival observed when the two types of exudates were compared. Therefore, polyphosphates used to enhance chicken quality aid in sustaining the numbers of
Campylobacter
bacteria, increasing the opportunity for disease via cross-contamination or improperly cooked poultry.
Rickettsia
Symbionts Cause Parthenogenetic Reproduction in the Parasitoid Wasp
Pnigalio soemius
(Hymenoptera: Eulophidae)
Authors: Giorgini M. , Bernardo U. , Monti M. M. , Nappo A. G. , Gebiola M.
Published: February 2010

Bacteria in the genus
Rickettsia
are intracellular symbionts of disparate groups of organisms. Some
Rickettsia
strains infect vertebrate animals and plants, where they cause diseases, but most strains are vertically inherited symbionts of invertebrates. In insects
Rickettsia
symbionts are known to have diverse effects on hosts ranging from influencing host fitness to manipulating reproduction. Here we provide evidence that a
Rickettsia
symbiont causes thelytokous parthenogenesis (in which mothers produce only daughters from unfertilized eggs) in a parasitoid wasp,
Pnigalio soemius
(Hymenoptera: Eulophidae). Feeding antibiotics to thelytokous female wasps resulted in production of progeny that were almost all males. Cloning and sequencing of a fragment of the 16S rRNA gene amplified with universal primers, diagnostic PCR screening of symbiont lineages associated with manipulation of reproduction, and fluorescence
in situ
hybridization (FISH) revealed that
Rickettsia
is always associated with thelytokous
P. soemius
and that no other bacteria that manipulate reproduction are present. Molecular analyses and FISH showed that
Rickettsia
is distributed in the reproductive tissues and is transovarially transmitted from mothers to offspring. Comparison of antibiotic-treated females and untreated females showed that infection had no cost. Phylogenetic analyses of 16S rRNA and
gltA
gene sequences placed the symbiont of
P. soemius
in the bellii group and indicated that there have been two separate origins of the parthenogenesis-inducing phenotype in the genus
Rickettsia
. A possible route for evolution of induction of parthenogenesis in the two distantly related
Rickettsia
lineages is discussed.
Mapping of Vps21 and HOPS Binding Sites in Vps8 and Effect of Binding Site Mutants on Endocytic Trafficking
Authors: Pawelec Agnes , Arsić Janja , Kölling Ralf
Published: February 2010

Vps8 is a subunit of the CORVET tethering complex, which is involved in early-to-late endosome fusion. Here, we examine the role of Vps8 in membrane fusion at late endosomes in
Saccharomyces cerevisiae
. We demonstrate that Vps8 associates with membranes and that this association is independent of the class C/HOPS core complex and, contrary to a previous report, also independent of the Rab GTPase Vps21. Our data indicate that Vps8 makes multiple contacts with membranes. One of these membrane binding regions could be mapped to the N-terminal part of the protein. By two-hybrid analysis, we obtained evidence for a physical interaction between Vps8 and the Rab5 homologue Vps21. In addition, the interaction with the HOPS core complex was confirmed by immunoprecipitation experiments. By deletion analysis, the Vps21 and HOPS binding sites were mapped in Vps8. Deletions that abrogated HOPS core complex binding had a strong effect on the turnover of the endocytic cargo protein Ste6 and on vacuolar sorting of carboxypeptidase Y. In contrast, deletions that abolished Vps21 binding showed only a modest effect. This suggests that the Vps21 interaction is not essential for endosomal trafficking but may be important for some other aspect of Vps8 function.
Use of the Kinase Inhibitor Analog 1NM-PP1 Reveals a Role for Toxoplasma gondii CDPK1 in the Invasion Step
Authors: Sugi Tatsuki , Kato Kentaro , Kobayashi Kyosuke , Watanabe Shumpei , Kurokawa Hitomi , Gong Haiyan , Pandey Kishor , Takemae Hitoshi , Akashi Hiroomi
Published: February 2010

Toxoplasma gondii
CDPK1 (TgCDPK1) was found to be the target of the toxoplasmocidal compound 1NM-PP1. When TgCDPK1 was mutated at position 128 from glycine to methionine, resistance was gained. Inhibition of gliding motility without inhibition of micronemal secretion by 1NM-PP1 suggests a function for TgCDPK1 in gliding motility.