, 2000; Park et al., 2003; Tanaka, 2004; Wanner, 2006; St-Onge et al., 2008; CT99021 solubility dmso Zhao et al., 2008). Scab disease harms a broad range of root crops, including potato, sweet potato, radish, carrot, sugar beet, and burdock (Loria et al., 1997), with potato scab disease especially causing large economic losses. Diseased potato tubers exhibit characteristic dark-brown, corky lesions. The ugly symptoms of the disease reduce the market value of crops,

causing economic difficulties for potato producers. The causative agents of potato scab disease are multiple species of the genus Streptomyces. Streptomyces scabiei, Streptomyces acidiscabiei, and Streptomyces turgidiscabiei are the most studied and well-known causal agents (Lambert & Loria, 1989a, b; Miyajima et al., 1998; Kers et al., 2005). To date, these are the only three species of potato scab pathogens reported in Japan. Recent studies

have shown a correlation between the amounts of these pathogens in soils and the incidence of the disease (Koyama et al., 2006; Manome et al., 2008), suggesting that decreasing the quantity of the pathogens in soils could mitigate scab disease damage. Over the decades, physicochemical approaches have been applied to control pathogens and scab disease. For example, methods to reduce soil pH were conventionally used to suppress the disease by inhibiting pathogen growth (Lacey & Wilson, 2001). Soil fumigation using agents Tanespimycin molecular weight such as chloropicrin (trichloronitromethane), which is detrimental to animal and human health (Ristaino & Averre, 1992), was also adopted to control potato scab disease. Biological control using antagonistic microorganisms is a sustainable and environmentally acceptable management method for numerous pathogens (Punja & Utkhede, 2003; Tian et al., 2007). In the case of potato scab disease, previous studies have mainly focused on antagonists against S. scabiei. Several Streptomyces sp. have learn more been shown to inhibit the growth of S. scabiei (Hayashida et al., 1988; Lorang et al., 1995; Beausejour et al., 2003). Bacillus sp. was also revealed to inhibit the growth and sporulation

of S. scabiei by secreting extracellular compounds (Han et al., 2005). McKenna et al. (2001) reported biological control using a bacteriophage infecting S. scabiei. However, there has only been one report of antagonists against S. turgidiscabiei (Hiltunen et al., 2009), and little is known about antagonists against S. acidiscabiei. In addition, as far as we know, no reports have revealed a fungal antagonist against potato scab pathogens. Fungi are common inhabitants of soil environments, and are generally easy to handle and mass-produce. For this reason, many biological agents using fungi are commercially available for the control of plant diseases, although potato scab disease is not one of them (Punja & Utkhede, 2003; Fravel, 2005; Han et al., 2005). It is also significant that fungi tend to be more resistant than bacteria to acidic conditions (Thompson et al.

Lovastatin was termed monacolin K when isolated from Monascus pilosus (Staunton & Weissman, 2001). A structurally related compound named compactin was isolated from Penicillium citrinum (Abe et al., 2002). Our PKS1 protein showed 36% similarity to both MokA in the monacolin K biosynthesis pathway (Chen et al., 2008) and compactin nonaketide synthase (CNKS) in the compactin biosynthesis selleck inhibitor pathway. The PKS1 protein also showed 37% sequence similarity to the PKS-NRPS hybrid equisetin synthetase (EqiS) in Fusarium heterosporum (Sims et al., 2005). LNKS contains a truncated NRPS module, and the biosynthesis of lovastatin and equisetin shares a common pathway up to the Diels–Alder

cyclization of hexaketide (Campbell & Vederas, 2010). Our PKS1 likely catalyzes a similar reaction, but the chain length of the polyketide cannot be predicted. The on-line software sbspks predicts that PKS1 accepts malonic or methylmalonic acid as a substrate, similar to LNKS and LDKS (Campbell & Vederas, 2010). There is a product template (PT) domain between the AT and ACP domains (Schuemann & Hertweck, 2009) controlling the chain length in non-reducing PKSs (Cox, 2007; Liu et al., 2011); however, the chain length determination in highly reduced PKSs, such as LNKS, LDKS and CNKS, is not well understood. The 760-bp fragment was located on an 11-kb hybrid pks-nrps gene (Fig. 3a). Hybrid gene clusters

are widely distributed in Ascomycetes (Collemare et al., 2008). The pks-nrps1

gene encodes a protein that displayed 36% similarity with three proteins: DmbS in the 2-pyridone 3MA desmethylbassianin (DMB) biosynthetic pathway (Heneghan et al., 2011), TenS in the tenellin biosynthetic pathway in B. bassiana (Eley et al., 2007), and FusS in the fusarin biosynthetic pathway in Fusarium moniliforme (teleomorph Gibberella moniliformis) (Song et al., 2004). sbspks predicts that malonic acid is the only accepted substrate for the AT domain of PKS-NRPS1. However, due to the highly variable signature sequences in the A domain binding pockets, we could not predict the substrates of all of the NRPSs reported here (Table S3). In the hybrid PKS-NRPS systems, the Dieckmann cyclase domain (also known as the R domain) often mediates product release (Halo et al., 2008; Du & Lou, 2010). Interestingly, the R domain of PKS-NRPS1 showed sequence similarity to the short-chain dehydrogenase/reductase Sorafenib concentration superfamily proteins in TenS, EqiS and DmbS (Halo et al., 2008; Sims & Schmidt, 2008; Heneghan et al., 2011) and therefore potentially mediates product release. Although PKS-NRPS1 contained an ER domain, it is likely to be inactive because there are three mutations in the reduced nicotinamide adenine dinucleotide phosphate (NADPH)-binding motif (Fig. S1). Although the ER domains of LNKS, TenS and DmbS are inactive, reduction was catalyzed via the trans-acting ERs encoded by lovC, tenC and dmbC, respectively (Eley et al., 2007; Ma et al., 2009; Heneghan et al., 2011).

Lovastatin was termed monacolin K when isolated from Monascus pilosus (Staunton & Weissman, 2001). A structurally related compound named compactin was isolated from Penicillium citrinum (Abe et al., 2002). Our PKS1 protein showed 36% similarity to both MokA in the monacolin K biosynthesis pathway (Chen et al., 2008) and compactin nonaketide synthase (CNKS) in the compactin biosynthesis Autophagy screening pathway. The PKS1 protein also showed 37% sequence similarity to the PKS-NRPS hybrid equisetin synthetase (EqiS) in Fusarium heterosporum (Sims et al., 2005). LNKS contains a truncated NRPS module, and the biosynthesis of lovastatin and equisetin shares a common pathway up to the Diels–Alder

cyclization of hexaketide (Campbell & Vederas, 2010). Our PKS1 likely catalyzes a similar reaction, but the chain length of the polyketide cannot be predicted. The on-line software sbspks predicts that PKS1 accepts malonic or methylmalonic acid as a substrate, similar to LNKS and LDKS (Campbell & Vederas, 2010). There is a product template (PT) domain between the AT and ACP domains (Schuemann & Hertweck, 2009) controlling the chain length in non-reducing PKSs (Cox, 2007; Liu et al., 2011); however, the chain length determination in highly reduced PKSs, such as LNKS, LDKS and CNKS, is not well understood. The 760-bp fragment was located on an 11-kb hybrid pks-nrps gene (Fig. 3a). Hybrid gene clusters

are widely distributed in Ascomycetes (Collemare et al., 2008). The pks-nrps1

gene encodes a protein that displayed 36% similarity with three proteins: DmbS in the 2-pyridone selleck compound desmethylbassianin (DMB) biosynthetic pathway (Heneghan et al., 2011), TenS in the tenellin biosynthetic pathway in B. bassiana (Eley et al., 2007), and FusS in the fusarin biosynthetic pathway in Fusarium moniliforme (teleomorph Gibberella moniliformis) (Song et al., 2004). sbspks predicts that malonic acid is the only accepted substrate for the AT domain of PKS-NRPS1. However, due to the highly variable signature sequences in the A domain binding pockets, we could not predict the substrates of all of the NRPSs reported here (Table S3). In the hybrid PKS-NRPS systems, the Dieckmann cyclase domain (also known as the R domain) often mediates product release (Halo et al., 2008; Du & Lou, 2010). Interestingly, the R domain of PKS-NRPS1 showed sequence similarity to the short-chain dehydrogenase/reductase Vasopressin Receptor superfamily proteins in TenS, EqiS and DmbS (Halo et al., 2008; Sims & Schmidt, 2008; Heneghan et al., 2011) and therefore potentially mediates product release. Although PKS-NRPS1 contained an ER domain, it is likely to be inactive because there are three mutations in the reduced nicotinamide adenine dinucleotide phosphate (NADPH)-binding motif (Fig. S1). Although the ER domains of LNKS, TenS and DmbS are inactive, reduction was catalyzed via the trans-acting ERs encoded by lovC, tenC and dmbC, respectively (Eley et al., 2007; Ma et al., 2009; Heneghan et al., 2011).

However, it is speculated that Gram-negative bacteria produce membrane-derived vesicles other than OMVs that originate from the inner membrane. A future study should determine whether membrane-derived vesicles from Gram-negative bacteria contain either OMVs, inner membrane vesicles or both. Klebsiella pneumoniae OMVs may interact with host cells and alter host cell biology, because these

Selleck Ibrutinib vesicular components contain numerous proteins, LPS and peptidoglycans. LPS-refractory epithelial HEp-2 cells and LPS-susceptible monocyte U937 cells were treated with different amounts of K. pneumoniae OMVs to determine whether K. pneumoniae OMVs induce morphological changes and growth inhibition of the host cells. No morphological changes (Fig. 2a) or inhibited cellular growth (Fig. 2b) were observed

in either cells treated with ≤ 50 μg mL−1 (protein concentration) OMVs. Two previous studies focusing on the host cell pathology induced by K. pneumoniae showed that extracellular components released or secreted from bacteria are partly associated with host cell cytotoxicity (Straus, 1987; click here Cano et al., 2009). Thus, we expected that K. pneumoniae OMVs would inhibit growth or induce death in either U937 cells, HEp-2 cells or both. However, OMVs from K. pneumoniae ATCC 13883 did not inhibit cell growth and were not cytotoxic to either cell type. In proteomic analysis of K. pneumoniae OMVs, we did not find any cytotoxic factors. These results suggest that OMVs from K. pneumoniae ATCC 13383 do not carry cytotoxic factors. However, whether OMVs from other K. pneumoniae strains are cytotoxic to host cells remains to be determined. To determine whether K. pneumoniae OMVs induce a proinflammatory response in vitro, HEp-2 cells were treated with 1–20 μg mL−1 (protein concentration) of K. pneumoniae OMVs for 24 h, and the expression of proinflammatory cytokine genes was analysed by RT-PCR. HEp-2 cells originating from human laryngeal

epithelial cells were used, because the respiratory tract is a common site Dapagliflozin for colonization of or infection by K. pneumoniae. HEp-2 cells were infected with live K. pneumoniae with a multiplicity of infection (MOI) of 1 or 10 as a positive control. Expression of IL-1β and IL-8 increased in a dose-dependent manner in respond to the K. pneumoniae OMVs (Fig. 3). MIP-1 expression was not increased. No expression of the IL-6 gene was observed (data not shown). These results indicate that K. pneumoniae OMVs elicit the expression of proinflammatory cytokine genes in epithelial cells. A proinflammatory response against OMVs has also been observed for several other Gram-negative pathogens, including Salmonella enterica serovar Typhimurium (Alaniz et al., 2007), H. pylori (Ismail et al., 2003), P. aeruginosa (Bauman & Kuehn, 2006; Ellis et al., 2010), Neisseria meningitidis (Durand et al., 2009) and Vibrio anguillarum (Hong et al., 2009).

Other factors on the Rm1021 cell surface, and growth conditions,

presumably regulate attachment and/or growth as a biofilm on polyvinylchloride. Rhizobia are soil bacteria with the capability to establish a symbiotic relationship with legume plants when soil nitrogen is limited. Rhizobial surface polysaccharides play important roles in symbiosis and formation of active nodules. Mutants defective in the production of exopolysaccharides, lipopolysaccharides, and capsular polysaccharides usually show reduced induction of effective nodules, and are particularly Selleck C59 wnt affected in the process of infection through infection threads (Hirsch, 1999). One of the best-studied exopolysaccharides produced by Sinorhizobium meliloti is succinoglycan (EPS I) (Reinhold et al., 1994), which consists of repeated units of an octasaccharide containing one galactose and seven glucoses, and has characteristic succinyl, acetyl, and pyruvyl modifications. A 25-kb region located in the second symbiotic megaplasmid (pSymB) in S. meliloti clusters the exo–exs genes necessary for the production of EPS I. The roles of most Kinase Inhibitor Library mouse of these genes have already been defined (Reuber & Walker, 1993). Sinorhizobium meliloti is also capable of producing a second exopolysaccharide known as galactoglucan (EPS II) (Her et al., 1990; Zevenhuizen, 1997), which is synthesized under

conditions of phosphate limitation (as often found in soils) (Zhan et al., 1991; Mendrygal & González, 2000), in the presence of a mutation in the regulatory gene mucR (Zhan Florfenicol et al., 1989; Keller et al., 1995) or an intact copy of the transcriptional

regulator expR (Glazebrook & Walker, 1989; Pellock et al., 2002). EPS II is a polymer of disaccharide repeating units consisting of an acetylated glucose and a pyruvylated galactose (Her et al., 1990). A 32-kb cluster of genes (the exp genes) also located in pSymB is responsible for the production of EPS II (Glazebrook & Walker, 1989). EPS I and EPS II are synthesized in two different fractions: high molecular weight (HMW) and low molecular weight (LMW). External addition of the LMW fractions of EPS I (trimers of the octasaccharide), and oligomers (15–20 units of the disaccharide) of EPS II, can restore defective infection phenotypes in exopolysaccharide mutants, indicating that the establishment of symbiosis requires the presence of at least one of the LMW forms of either EPS I or EPS II (Battisti et al., 1992; González et al., 1996). Bacterial surface components, such as exopolysaccharides, flagella, and lipopolysaccharides, are important not only in rhizobia–legume symbiosis but also in biofilm formation. Biofilms are defined as microbial communities surrounded by a self-produced polymeric matrix and attached to a surface (Costerton et al., 1995). The major components of biofilms are water (up to 97% of the total volume) and bacterial cells.

Our results show that a hierarchical distributed network is synchronized between individuals during the processing of extended musical sequences, and provide new insight

into the temporal integration of complex and biologically salient auditory sequences. Music is a cultural universal and a rich part of the human experience. Brain imaging studies have identified an array of structures that underlie critical components of music, including pitch (Zatorre et al., 1994; Patel & Balaban, 2001), harmony (Janata et al., 2002; Passynkova et al., 2005), rhythm (Snyder & Large, 2005; Grahn & Rowe, 2009), timbre (Menon et al., 2002; Deike et al., 2004) and musical syntax (Levitin & Menon, 2005; Abrams et al., 2011; Oechslin et al., 2012). A drawback of probing neural substrates of www.selleckchem.com/products/gsk126.html individual musical features is that artificially CHIR-99021 cost constructed laboratory stimuli do not represent music as it is commonly heard, limiting the ecological validity of such studies. Furthermore, this componential approach fails to tap into one of the most important aspects of listeners’ musicality – the ability to integrate components of musical information over extended time periods (on the order of minutes)

into a coherent perceptual gestalt (Leaver et al., 2009). Examining the synchronization of brain responses across listeners constitutes a novel approach for exploring neural substrates of musical information processing. Inter-subject synchronization (ISS) using functional magnetic resonance imaging

(fMRI) detects common stimulus-driven brain structures by calculating voxel-wise correlations in fMRI activity over time between subjects (Hasson et al., 2004). The theoretical basis for using this approach is that brain structures that are consistently synchronized across subjects during an extended stimulus constitute core brain regions responsible for tracking structural elements of that stimulus over time (Hasson et al., 2010). ISS represents a fundamentally different approach, and provides advantages, relative to conventional fMRI methods Dichloromethane dehalogenase (Wilson et al., 2008; see Fig. S1). ISS allows us to examine cognitive processes that require the integration of information over extended time periods; this is critical for the study of music in which the structure of musical elements is manifested over time. Furthermore, ISS does not rely on a priori assumptions about specific stimulus events or subtraction paradigms that require comparison of discrete perceptual or cognitive events. Our goal was to examine shared neural representations underlying the processing of natural musical stimuli (‘Natural Music’; Fig. 1). We used ISS to identify brain regions that showed synchronized activity across individuals in response to music.

Manuscripts published prior to 2004 tended not to specify a study design as they primarily described clinical programmes. In the nine studies published after 2004 that did declare a study design, only in five cases did the listed study design agree with a study design

that would have been ascribed using Cochrane Collaboration guidelines.[35] Over time, manuscripts BGB324 about HIV pharmacists increasingly included CD4+ cell counts, HIV viral load and adherence as outcome measures (15% in papers published prior to 2004 versus 53% in papers published in 2004 and after). Manuscripts that measured adherence as an outcome typically described the adherence calculation well (8 of 9 studies) and most manuscripts provided some information about the study pharmacist’s qualifications or background training LY2606368 (11 of 22 studies). Our search found that the majority of research studies evaluating HIV pharmacist interventions used pre-post observational study designs. After 2004, these observational studies began to examine the impact of pharmacist services on HIV clinical outcomes such as CD4+ cell count and HIV viral load.[4] Despite these enhancements, published observational studies of HIV pharmacists failed to report a substantial

amount of critical information suggested by established manuscript guidelines. Randomized studies of HIV pharmacist interventions represent an even greater step forward towards demonstrating the value of HIV pharmacists. Yet, there did not appear to be an increasing trend in publication of rigorous randomized studies of HIV pharmacists as only three of these studies were identified (2004, 2005 and 2010) and included in our evaluation. In general, adequacy of reporting critical information was much improved in these three papers, and pertinent HIV clinical outcomes were often included as primary or secondary measures. One limitation to our study is that most of the manuscripts we evaluated were published prior to the availability of the STROBE and CONSORT

guidelines, or were very published in journals that do not endorse these guidelines. Our review illustrates where HIV pharmacist literature stands under current reporting recommendations, and identifies areas where HIV pharmacist literature might continue to improve in reporting. This is a moving target because good reporting principles may evolve over time. Many of the observational studies we evaluated were descriptive and did not include a comparator group. STROBE criteria may be more applicable to observational cohorts with more than one group. Various tools to evaluate reporting in observational or non-randomized study designs exist, and our evaluation was limited only to STROBE. Though CONSORT guides the interpretation of its criteria with supportive explanations, STROBE criteria were more subject to interpretation.

Manuscripts published prior to 2004 tended not to specify a study design as they primarily described clinical programmes. In the nine studies published after 2004 that did declare a study design, only in five cases did the listed study design agree with a study design

that would have been ascribed using Cochrane Collaboration guidelines.[35] Over time, manuscripts buy Sirolimus about HIV pharmacists increasingly included CD4+ cell counts, HIV viral load and adherence as outcome measures (15% in papers published prior to 2004 versus 53% in papers published in 2004 and after). Manuscripts that measured adherence as an outcome typically described the adherence calculation well (8 of 9 studies) and most manuscripts provided some information about the study pharmacist’s qualifications or background training Trichostatin A mw (11 of 22 studies). Our search found that the majority of research studies evaluating HIV pharmacist interventions used pre-post observational study designs. After 2004, these observational studies began to examine the impact of pharmacist services on HIV clinical outcomes such as CD4+ cell count and HIV viral load.[4] Despite these enhancements, published observational studies of HIV pharmacists failed to report a substantial

amount of critical information suggested by established manuscript guidelines. Randomized studies of HIV pharmacist interventions represent an even greater step forward towards demonstrating the value of HIV pharmacists. Yet, there did not appear to be an increasing trend in publication of rigorous randomized studies of HIV pharmacists as only three of these studies were identified (2004, 2005 and 2010) and included in our evaluation. In general, adequacy of reporting critical information was much improved in these three papers, and pertinent HIV clinical outcomes were often included as primary or secondary measures. One limitation to our study is that most of the manuscripts we evaluated were published prior to the availability of the STROBE and CONSORT

guidelines, or were Janus kinase (JAK) published in journals that do not endorse these guidelines. Our review illustrates where HIV pharmacist literature stands under current reporting recommendations, and identifies areas where HIV pharmacist literature might continue to improve in reporting. This is a moving target because good reporting principles may evolve over time. Many of the observational studies we evaluated were descriptive and did not include a comparator group. STROBE criteria may be more applicable to observational cohorts with more than one group. Various tools to evaluate reporting in observational or non-randomized study designs exist, and our evaluation was limited only to STROBE. Though CONSORT guides the interpretation of its criteria with supportive explanations, STROBE criteria were more subject to interpretation.

These results demonstrated that the lateral diffusion of AMPA receptors was a novel postsynaptic mechanism influencing short-term plasticity of individual synapses. Interestingly, the diffusion rates of AMPA receptors on dissociated hippocampal neurons

decreased during synapse maturation, between the second and third week in vitro (Borgdorff & Choquet, 2002). During this time period, a hyaluronan–CSPG-based ECM resembling the perisynaptic net-like ECM of the adult CNS is formed in these cultures (John et al., 2006). Similar to the in vivo situation, the net-like structure divides the neuronal surface into multiple compartments of variable size (Fig. 1, see above). These ECM-derived cell surface structures restrict the lateral diffusion of extrasynaptic AMPA receptors (Frischknecht et al., 2009).

Removal FDA-approved Drug Library mouse MK-1775 mouse of the ECM with the enzyme hyaluronidase increased diffusion rates of extrasynaptic receptors and the exchange rate between synaptic and extrasynaptic receptors. This resembles the ‘juvenile’ situation before the ECM is established in the cultures (day 10 in vitro). An electrophysiological examination revealed that removal of ECM from dissociated hippocampal neurons affected short-term synaptic Histidine ammonia-lyase plasticity, i.e., in the presence of the ECM, PPD seems to be much stronger than after hyaluronidase treatment, when basically no PPD was observed. A similar down-regulation of AMPAR movement during synaptic maturation was observed when studying the role of stargazin in controlling AMPAR immobilization. Interestingly, overexpression in mature neurons of mutant stargazin unable to bind their intracellular partner PSD-95 reverted to the behavior of AMPAR to ‘juvenile’ type (Bats et al., 2007). Consequently, both intracellular and ECM-derived surface compartments can influence short-term plasticity of neurons by controlling lateral diffusion and thus control the synaptic availability

of naïve AMPA receptors. It should be noted here that ECM nets are not impermeable barriers for diffusing surface proteins. They rather have to be considered as viscous structures that reduce the surface mobility of proteins. Accordingly, the size and shape of the extracellular domains of surface-exposed membrane proteins influences the mobility shift by the ECM (Frischknecht et al., 2009). Along this line, the recent characterization of the full crystal structure of AMPARs points to their very large extracellular domain, protruding over 10 nm into the extracellular space (Sobolevsky et al., 2009) and thus likely to bump into the ECM components.

One hundred and forty soil samples, collected from 30-cm soil depth in Nampong District, Khon Kaen Province, Thailand, were used for phage isolation using the basic enrichment method see more (Kutter & Sulakvelidze, 2005). Five grams of soil were inoculated into 20 mL of brain–heart infusion broth (Oxoid, Basingstoke, UK), mixed and incubated at 37 °C for 16–18 h.

Five milliliters of the culture were centrifuged at 4000 g, 4 °C for 30 min and the supernatant filtered through 0.22-μm filters and used as phage lysate or stored at 4 °C until use. The spot test method was used to screen for the presence of lytic phage activity (Chopin et al., 1976). Approximately 1 mL of mid-log phase B. pseudomallei P37 (1 × 109 CFU mL−1) was flooded onto a plate containing nutrient agar with 3.6 mM CaCl2, the excess removed and allowed to dry open in a laminar flow biosafety cabinet. Twenty microliters of phage lysate from each soil sample were then dropped

onto the plate and incubated at 37 °C overnight and the clear zone formation was observed. Each clear and isolated plaque was cored out by a sterile Pasteur pipette into nutrient broth, shaken for 1 h and centrifuged at 2500 g, at 4 °C for 20 min. Supernatants were filtered through 0.22-μm filter membranes and purified by the Gamma-secretase inhibitor soft agar method (Sambrook & Russell, 2001). The purification steps for each phage were repeated three times to ensure the homogeneity of the phage stock and finally phage titers were calculated as PFU mL−1. A tuclazepam mid-log phase culture of B. pseudomallei P37 (1 × 109 CFU mL−1) in 100 mL nutrient broth (Oxoid) containing 3.6 mM CaCl2 was mixed with the purified phage suspension at a multiplicity of infection (MOI) of 0.1 and incubated at 37 °C for 3–5 h. After bacterial lysis was observed, the solution was centrifuged and the supernatant containing phage particles was filtered through

0.22-μm filter membranes and used as the phage suspension. One hundred microliters of each B. pseudomallei isolate’s overnight culture were spread on the surface of nutrient agar plates and 20 μL of each phage suspension (∼108–109 PFU mL−1) was spotted and incubated at 37 °C for 18–24 h. The results were recorded as negative if there were no plaques and positive if clear plaques were observed. The host range of selected phages was further evaluated with species closely related to Burkholderia (Table 1) by the agar overlay method (Sambrook & Russell, 2001). The negative staining method was performed to visualize phage morphology using transmission electron microscopy (Jamalludeen et al., 2007). Ten microliters of phage suspension (>108 particles mL−1) were used for staining with 10 μL of 2% uranyl acetate for 10 min. Photographs were taken under a transmission electron microscope (JEM-2100, JEOL LAB6, Japan). Size was determined from the average of three independent measurements.