Abbreviations EEG electroencephalography VEP visual evoked potential “
“Our attention to a sensory cue of a given modality interferes with attention to a sensory cue of another modality. However, an object emitting various sensory cues attracts attention more effectively. The thalamic reticular nucleus (TRN) could play a pivotal role in such cross-modal modulation of attention given that cross-modal sensory interaction takes place in the TRN, because the TRN occupies a highly strategic position to function in the control of gain and/or gating of sensory processing

http://www.selleckchem.com/products/AG-014699.html in the thalamocortical loop. In the present study cross-modal interactions between visual and auditory inputs were examined in single TRN cells of anesthetised rats using juxta-cellular recording and labeling techniques. Visual selleck or auditory responses were modulated by subthreshold sound or light stimuli, respectively, in the majority of recordings (46 of 54 visual and 60 of 73 auditory cells). However, few bimodal sensory cells were found. Cells showing modulation of the sensory response

were distributed in the whole visual and auditory sectors of the TRN. Modulated cells sent axonal projections to first-order or higher-order thalamic nuclei. Suppression predominated in modulation that took place not only in primary responses but also in late responses repeatedly evoked after sensory stimulation. Combined sensory stimulation also evoked de-novo responses, and modulated response latency and burst spiking. These results indicate that the TRN incorporates sensory inputs of different modalities into single cell activity to function in sensory processing in the lemniscal and non-lemniscal systems. This raises the possibility that the TRN constitutes neural pathways involved in cross-modal attentional gating. “
“There are opposing views about the status of layer IV in the primary motor cortex

(area 4). Cajal described a layer IV in area 4 of adult humans. In contrast, Brodmann found layer IV in developmental but not in adult primates and called area 4 ‘agranular’. We addressed this issue in rhesus monkeys using the neural Molecular motor marker SMI-32, which labels neurons in lower layer III and upper layer V, but not in layer IV. SMI-32 delineated a central unlabeled cortical stripe in area 4 that corresponds to layer IV, which was populated with small interneurons also found in layer IV in ‘granular’ areas (such as area 46). We distinguished layer IV interneurons from projection neurons in the layers above and below using cellular criteria. The commonly used term ‘agranular’ for area 4 is also used for the phylogenetically ancient limbic cortices, confusing areas that differ markedly in laminar structure. This issue pertains to the systematic variation in the architecture across cortices, traced from limbic cortices through areas with increasingly more elaborate laminar structure. The principle of systematic variation can be used to predict laminar patterns of connections across cortical systems.

“
“The aim of the study was to compare prospectively indicator-condition (IC)-guided testing versus testing of those with non-indicator conditions (NICs) in four primary care centres (PCCs) in Barcelona, Spain. From October 2009 to February 2011, patients aged from 18 to 65

years old who attended a PCC for a new herpes zoster infection, seborrhoeic eczema, mononucleosis syndrome or leucopenia/thrombopenia were included in the IC group, and one in every 10 randomly selected patients consulting for other reasons were included in the NIC group. A proportion of patients in each group were offered an HIV test; those who agreed to be tested were given a rapid finger-stick HIV test (€6 per test). Epidemiological and clinical

data were collected and analysed. During the study period, 775 patients attended with one of the four selected ICs, while 66 043 patients presented with an NIC. HIV screening was offered to 89 patients with ICs (offer rate LDE225 datasheet 11.5%), of whom 85 agreed to and completed testing (94.4 and 100% acceptance and completion rates, respectively). In the NIC Nutlin-3a research buy group, an HIV test was offered to 344 persons (offer rate 5.2%), of whom 313 accepted (90.9%) and 304 completed (97.1%) testing. HIV tests were positive in four persons [prevalence 4.7%; 95% confidence interval (CI) 1.3–11.6%] in the IC group and in one person in the NIC group (prevalence 0.3%; 95% CI 0.01–1.82%; P < 0.009). If every eligible person had taken an HIV test, we would have spent €4650 in the IC group and €396 258 in the NIC group, and an estimated 36 (95% CI 25–49) and 198 persons (95% CI 171–227), respectively, would have been diagnosed with HIV infection. The estimated cost per new HIV diagnosis would Bcl-w have

been €129 (95% CI €107–153) in the IC group and €2001 (95% CI €1913–2088) in the NIC group. Although the number of patients included in the study was small and the results should be treated with caution, IC-guided HIV testing, based on four selected ICs, in PCCs seems to be a more feasible and less expensive strategy to improve diagnosis of HIV infection in Spain than a nontargeted HIV testing strategy. The large majority of sexually transmitted infection (STI) prevention, diagnosis, and treatment occurs in primary care centres (PCCs) [1, 2]. In Spain, access to the health service is universal and free, and PCCs are the settings most frequently visited in order to take an HIV test (approximately 30% of all HIV tests are carried out in PCCs) [3, 4], and where 72% of people receive health care at least once a year [5]. As such, they appear to be suitable settings for HIV screening strategies [6]. Moreover, as a consequence of the reduction in morbidity and mortality in HIV-infected patients associated with highly active antiretroviral therapy, an increased number of patients have stable, chronic HIV infection, and this health care challenge may require new approaches.

Cell-free culture supernatants were investigated for antibacterial activity using the well-diffusion buy Cyclopamine assay. About 3% of haemolymph-associated cultivable bacteria displayed antibacterial activity toward Gram-negative pathogens. Among the active bacteria, Pseudoalteromonas strains exhibited the highest antibacterial activity. The cell-free culture supernatant of one of them, named hCg-51, was able to inhibit the growth of bacterial pathogens even after drastic dilution (1 : 1024). Hemocyte survival was not significantly altered in the presence of the haemolymph-associated

strains assayed. Moreover, a dose-dependent beneficial effect on hemocyte survival rates was observed with the hCg-51 strain. These results suggest that haemolymph microbiota may participate in bivalve protection and therefore XL184 mouse confer a health benefit on the host. As a result, the results highlight bivalve haemolymph microbiota as a promising novel source for aquaculture probiotics. This work also gives a first insight into the contribution of the haemolymph-associated microbiota as part of the bivalve ‘hologenome’. The ‘hologenome’ concept

was introduced by Zilber-Rosenberg & Rosenberg (2008). It considers the host and its associated microorganisms (microbiota) a super-organism (holobiont) and therefore the true evolutionary unit of selection. This concept is based on (1) existing symbiotic relationships between all animals or plants and several microorganisms; (2) the transmission of the symbiotes; (3) the benefits of the symbiotic association between the host and the microorganisms; and (4) the genetic plasticity enhancement of the holobiont, through change VAV2 in the microbiotic composition under environmental pressure (Zilber-Rosenberg & Rosenberg, 2008). The ‘hologenome’ theory strengthens the probiotic concept. Microbiota

may form a microbial shield that could limit the settlement of pathogens by competition for resources and/or antimicrobial compound production and/or stimulation of the host immune system (Oelschlaeger, 2010). Microbiota antimicrobial compounds seem to play a key role in control of the microbial community and health recovery (Dobson et al., 2012). As environmental pressures such as climate changes can disturb the microbial shield, allowing epizootic events in marine invertebrates, antimicrobial compounds from autochthonous probiotics could be a powerful tool to restore the microbial shield and protect the host from pathogens (Desriac et al., 2010). Marine invertebrates and especially bivalves may be considered pertinent animal models since they are filter-feeders and so have to face large numbers of microorganisms. Furthermore, the well-accepted presence of microorganisms in the haemolymph of healthy bivalves tends to indicate that this ecosystem could contribute to host haemostasis.

cerevisiae and S. pombe? In S. cerevisiae, Dam1 can form MT attachment site if it is targeted by tethering to an ectopic noncentromeric DNA sequence (Kiermaier et al., 2009; Lacefield et al., 2009). It will also be interesting to study what happens if Dam1 is targeted to such an ectopic location in S. pombe or C. albicans where the CEN formation is epigenetically regulated. It is important Selleckchem Crizotinib to note that the localization dependence studies were not performed uniformly as the sensitivity of quantitative measurement techniques improved significantly

over the years. Moreover, the methods used to assay KT localization dependence are sometimes not mentioned clearly, and in many occasions, the methods are rather qualitative than quantitative. For example, the CENP-A independent localization of Mis12 at the CEN in fission yeast has been claimed based on an experiment that was not shown (Takahashi et al., 2000). Unfortunately, this information was cited in several subsequent publications. This unconfirmed observation was sometimes even considered as a variant feature of fission yeast. Similar observations have been reported in localization dependence studies performed in other organisms

as well (Cheeseman et al., 2004; Przewloka et al., 2007). These questions should be readdressed with the Selleckchem Ion Channel Ligand Library help of more sensitive assays in uniform experimental conditions in a variety of model systems. The outcome of these experiments will help us to precisely compare and contrast the KT structure and its function across species. The contrasting

results of an identical question can occur due to the differences in experimental conditions or measurement techniques. For an example, localization dependence of Dsn1 on Mtw1 in S. cerevisiae is contradictory Interleukin-3 receptor in two reports (De Wulf et al., 2003; Pinsky et al., 2003). More quantitative assays to determine the actual scenario are required in such cases to resolve these apparent discrepancies. It is evident that although most of the proteins assemble at the CEN are functionally conserved across species, the CEN DNA is diverged even in closely related species. Comparative genomic analyses in different yeasts revealed that the CEN DNA is hyper-variable even in closely related species (Bensasson et al., 2008; Padmanabhan et al., 2008; Rhind et al., 2011). The phenomenon of hyper-variability of the DNA sequence at the CEN despite its conserved function in chromosome segregation was previously designated as the ‘centromere paradox’ (Henikoff et al., 2001). In this review, we analysed the similarities and differences in the process of KT assembly in yeasts. While the organization of a KT is conserved, there appears to be subtle divergence in regulation of KT assembly in these organisms. Whether this process has evolved uniquely in different organisms to keep pace with the fast evolving CEN DNA is not clear.

The TDF is a useful tool for grouping adherence barriers; patients have endorsed the relevance of literature-identified adherence barriers and provided useful anecdotes to further inform practice. Non-adherence to prescribed selleckchem medicines is of notable concern and a priority for pharmacy practice research. Whilst there is ample literature to report barriers to medication adherence in chronic conditions, a recent synthesis

of this literature is lacking, as is a cohesive, theory-based strategy for grouping medication adherence barriers. The Theoretical Domains Framework (TDF) is a composite of health psychology theory, designed to offer a structured approach for exploring the determinants of behaviour. Within this framework, key determinants of behaviour are grouped into behavioural domains such as skills, beliefs about capabilities and emotions.1 Medication Alpelisib adherence barriers were identified through a literature review and mapped to the behavioural domains of the TDF. University ethical approval was granted for the consultation exercises. Members of the public taking medicines for the prevention of cardiovascular disease (CVD) were purposively sampled from volunteers responding to a university-based recruitment strategy using

internal communication systems and social media that extended to the local community. The participants discussed the relevance of the literature-identified adherence barriers and the mapping of these to the TDF in two consultation exercises. These consultations Fludarabine concentration were audio-recorded, transcribed, and themed according to the behavioural domains of the TDF. Sixty medication adherence barriers were discussed across the following TDF behavioural domains; knowledge, skills, memory attention

and decision making processes, social influences, environmental constraints, emotions, motivation and goals, beliefs about consequences, beliefs about capabilities and the newly created goal conflicts. Two consultation exercises were undertaken, with five participants in the first and nine in the second. All participants were prescribed at least one medication for the prevention of CVD; the median number of medicines prescribed was 2 (IQR = 2–5). Eight (57%) participants were male and the median age was 66 (52 to 74) years. Participants understood the concept of grouping the adherence barriers according to the theoretical domains of the TDF and could relate the majority of the literature-identified barriers to their own experiences. The exceptions to this were barriers relating to fear of discrimination (emotions behavioural domain) and feeling embarrassed by taking medicines (social norms behavioural domain. Patient narratives provided an enhanced understanding about the ways in which medication adherence barriers can manifest.

“
“Uropathogenic Escherichia coli (UPEC) strains are among the most prevalent causative agents of urinary tract infections. To establish infection, UPEC must overcome the bactericidal action of host antimicrobial peptides. Previously, the enterohaemorrhagic E. coli outer membrane protease, OmpT, was shown to degrade and inactivate the human antimicrobial peptide LL-37. This study aims to investigate the involvement of UPEC OmpT in LL-37 degradation. An ompT deletion Navitoclax concentration mutant was generated in the prototypical UPEC strain CFT073. Western blot analysis showed that the OmpT protein level is moderate

in CFT073. In agreement, OmpT was shown to partially cleave LL-37. However, no difference in the minimum inhibitory concentration of LL-37 was observed between CFT073 and the ompT mutant. Plasmid complementation of ompT, which led to increased OmpT levels, resulted in complete cleavage of LL-37 and a fourfold increase in the minimum inhibitory concentration. The analysis of other UPEC isolates showed similar OmpT activity levels as CFT073. Although UPEC OmpT can cleave LL-37, we conclude that the low level of OmpT limits its contribution to LL-37 resistance. Collectively, these data suggest that UPEC OmpT is likely accompanied by other LL-37 resistance mechanisms. “
“Lactic acid

bacteria (LAB) are responsible for different types Z-VAD-FMK molecular weight of food fermentations that provide humans with many different classes of fermented products. During the 20th century, some

LAB strains as well as several members of the genus Bifidobacterium started to be extensively used in human nutrition as probiotics Evodiamine because of their health-promoting effects. Nowadays, the subset of extracellular proteins is being investigated as potential mediators of the process known as bacteria–host molecular crosstalk. Inclusion of human cecum extracts in laboratory culture medium modified the production of extracellular proteins by food and probiotic microorganisms. By proteomic and genetic means, the specific overproduction of two proteins was revealed to occur at transcriptional level. This work sheds light on the potential molecular effectors that food bacteria could use for interacting with the human gut and revealed that they may be produced under very specific environmental conditions. Lactic acid bacteria (LAB) have been part of human nutrition since ancient times, being involved in the production of an endless number of fermented products. These fermented foods play important roles in human customs. It is generally accepted that LAB were initially responsible for spontaneous food fermentations, some strains being selected by humans with the aim of controlling these spontaneous processes.

, 1998) at the SacII/XbaI site (for the 5′-flanking region) and the EcoRI/SalI site (for the 5′-portion of CDS) of p97CGH (Nakayama et al., 1998), resulting in the plasmid p97RAM2. Approximately a 2.5-kb DNA fragment obtained by

digesting p97RAM2 with SacII and SalI was used to transform ACG4 (Nakayama et al., 1998); the resulting strains were designated tet-RAM2. Primers RAM2CHA (nt −750 to −731) and RAM2CHB (nt 385–405) were used to confirm the correct integration sites (data not shown). For ERG20, the 5′-flanking region (nt −457 to −217) or the 5′-CDS region (nt −6 to 350) of ERG20 was amplified with PCR using the primers ERG20AF and ERG20AR or ERG20BF and ERG20BR, respectively. Both amplified fragments of ERG20 were digested at the SacII/XbaI site (for the 5′-flanking find more region) and the MunI/SalI site (for the 5′-portion of CDS) and cloned into the SacII/XbaI site (for region A) and the EcoRI/SalI site (for region B) of p97CGH to facilitate ligation to the CgHIS3-97t, resulting in plasmid p97ERG20. Approximately a 2.5-kb DNA fragment obtained by digesting p97ERG20 with SacII and SalI was used to transform ACG4; the resulting strains were designated tet-ERG20.

Integration at the correct genomic site was confirmed by PCR using the primers ERG20CHA (nt −666 to −648) and ERG20CHB (nt 483–503) (data not shown). The primers used in this study are listed in Table 2. For time-course experiments, approximately 104 mutant cells mL−1 were inoculated and cultured in YEPD medium at 37 °C with or without 10 μg mL−1 of doxycycline. Growth was monitored Selleckchem Metformin by measuring OD600 nm at indicated times after adding doxycycline. The number of viable cells was determined NADPH-cytochrome-c2 reductase by counting aliquots of individual colonies on agar plates after incubation for 24 h at 37 °C. For measuring growth in serum-, FPP- or GPP-containing media, approximately 103 cells (200 μL) were inoculated and cultured in YEPD medium at 37 °C for 14 h, with or without 10 μg mL−1 of doxycycline, and in the presence of various concentrations of human serum (Irvine Scientific), FPP (Sigma-Aldrich) or GPP (Sigma-Aldrich). Male CD-1 mice

were immunocompromised by injecting cyclophosphamide (200 mg kg−1) 3 days before infection and 100 mg kg−1 0, 3, 7 and 11 days after infection. In addition to cyclophosphamide, mice were also coinjected with 125 mg kg−1 cortisone acetate. Each mouse was intravenously inoculated with 105C. glabrata cells, and administered doxycycline (2 mg mL−1), dissolved in a 5% sucrose solution, as drinking water 6 days before infection. At indicated times, 0 or 14 days after infection, mice were killed, and their kidneys were removed and homogenized. The homogenates were spread on YEPD agar plates containing penicillin G (200 U mL−1) and streptomycin (200 μg mL−1). After a 24-h incubation at 37 °C, the number of yeast colonies appearing on agar plates was counted.

Recently, C9-1 has been reassigned from find more P. agglomerans to the novel species P. vagans based on its gyrB sequence

(Brady et al., 2009; Rezzonico et al., 2009). Pantoea agglomerans and P. vagans isolates are generally considered nonpathogenic. Most P. agglomerans isolates lack virulence determinants such as type III secretion systems (T3SS), while some contain a T3SS described as a nonpathogenic type (Rezzonico et al., 2009). The phytopathogenicity of subspecies P. agglomerans pv. gypsophilae and pv. betae can be attributed to recently acquired large plasmids that carry a pathogenic type of T3SS and other virulence determinants (Ezra et al., 2000; Mor et al., 2001; Guo et al., 2002; Manulis & Barash, 2003; Nissan et IDH inhibitor al., 2006). Virulence and ecological fitness genes in phytopathogenic P. agglomerans pathovars, Pantoea stewartii and Pantoea ananatis are regulated by an autoinducer-1 quorum-sensing system involving N-acyl-homoserine lactone (AHL) signals (von Bodman et al., 2003; Morohoshi et al., 2007; Chalupowicz et al., 2008, 2009). Several Pantoea species are yellow pigmented (Grimont & Grimont, 2005) due to production of carotenoids (Sandmann et al., 1990; Hundle et al., 1994). Nonpigmented variants have been reported, arising spontaneously at a low frequency (10−2–10−3) after extended cultivation on nutrient-rich laboratory media (Chatterjee

& Gibbins, 1971; Gantotti & Beer, 1982; Lindh et al., 1991). These reports described physiological changes, such as thiamine deficiency and negative reactions with citrate or maltose, and lack of

reversion to a wild-type phenotype, suggesting that such phenotypic changes are due to plasmid loss, although this has never been confirmed experimentally. We have found that P. vagans C9-1 carries three plasmids: two plasmids of 168 kb (pPag1) and 166 kb (pPag2), and the 530-kb megaplasmid named pPag3 (Smits et al., 2009). The phenotypic effects of these plasmids in P. vagans C9-1 have not been described previously. Sequence analysis of the megaplasmid revealed that carotenoid biosynthesis Thymidylate synthase is encoded on plasmid pPag3. We obtained a nonpigmented variant of P. vagans C9-1 that lost the ability to synthesize thiamine and metabolize maltose, features that were also encoded by plasmid pPag3 genes. The aim of this study was to use the nonpigmented variant that lacks pPag3, representing over 10% of the total genome, in order to confirm functional phenotypes for annotated plasmid genes. Bacteria were routinely grown at 28 °C on Luria–Bertani (LB) (Sambrook et al., 1989). Carbon source (glucose, sorbitol, maltose or sucrose) and thiamine (5 μg mL−1) utilization assays were conducted in amended M9 minimal medium (Sambrook et al., 1989). Resistance to ampicillin (2.5–200 μg mL−1) or tellurite (50 μg mL−1) was determined on amended LB agar.

Recently, C9-1 has been reassigned from find more P. agglomerans to the novel species P. vagans based on its gyrB sequence

(Brady et al., 2009; Rezzonico et al., 2009). Pantoea agglomerans and P. vagans isolates are generally considered nonpathogenic. Most P. agglomerans isolates lack virulence determinants such as type III secretion systems (T3SS), while some contain a T3SS described as a nonpathogenic type (Rezzonico et al., 2009). The phytopathogenicity of subspecies P. agglomerans pv. gypsophilae and pv. betae can be attributed to recently acquired large plasmids that carry a pathogenic type of T3SS and other virulence determinants (Ezra et al., 2000; Mor et al., 2001; Guo et al., 2002; Manulis & Barash, 2003; Nissan et Selleckchem Epacadostat al., 2006). Virulence and ecological fitness genes in phytopathogenic P. agglomerans pathovars, Pantoea stewartii and Pantoea ananatis are regulated by an autoinducer-1 quorum-sensing system involving N-acyl-homoserine lactone (AHL) signals (von Bodman et al., 2003; Morohoshi et al., 2007; Chalupowicz et al., 2008, 2009). Several Pantoea species are yellow pigmented (Grimont & Grimont, 2005) due to production of carotenoids (Sandmann et al., 1990; Hundle et al., 1994). Nonpigmented variants have been reported, arising spontaneously at a low frequency (10−2–10−3) after extended cultivation on nutrient-rich laboratory media (Chatterjee

& Gibbins, 1971; Gantotti & Beer, 1982; Lindh et al., 1991). These reports described physiological changes, such as thiamine deficiency and negative reactions with citrate or maltose, and lack of

reversion to a wild-type phenotype, suggesting that such phenotypic changes are due to plasmid loss, although this has never been confirmed experimentally. We have found that P. vagans C9-1 carries three plasmids: two plasmids of 168 kb (pPag1) and 166 kb (pPag2), and the 530-kb megaplasmid named pPag3 (Smits et al., 2009). The phenotypic effects of these plasmids in P. vagans C9-1 have not been described previously. Sequence analysis of the megaplasmid revealed that carotenoid biosynthesis PAK5 is encoded on plasmid pPag3. We obtained a nonpigmented variant of P. vagans C9-1 that lost the ability to synthesize thiamine and metabolize maltose, features that were also encoded by plasmid pPag3 genes. The aim of this study was to use the nonpigmented variant that lacks pPag3, representing over 10% of the total genome, in order to confirm functional phenotypes for annotated plasmid genes. Bacteria were routinely grown at 28 °C on Luria–Bertani (LB) (Sambrook et al., 1989). Carbon source (glucose, sorbitol, maltose or sucrose) and thiamine (5 μg mL−1) utilization assays were conducted in amended M9 minimal medium (Sambrook et al., 1989). Resistance to ampicillin (2.5–200 μg mL−1) or tellurite (50 μg mL−1) was determined on amended LB agar.

The nodules lacked lenticels and fixed two times less nitrogen (Rojas-Jiménez et al., 2005). The three R. tropici mutants (ΔolsC, ΔolsE, and ΔolsCΔolsE) lacking OL hydroxylases established their symbiosis only poorly (Vences-Guzmán et al., 2011). As R. tropici is challenged by low pH conditions inside its host plant (Udvardi et al., 1991; Udvardi & Day, 1997), it can be speculated that the observed symbiotic phenotype

is a consequence of the mutants’ increased acid sensitivity. The OL hydroxylase OlsD was first isolated from B. cenocepacia J2315, a β-proteobacterium known as an opportunistic pathogen of humans. González-Silva et al. (2011) originally suggested that 2-hydroxylation of OLs in B. cenocepacia might be performed by an LpxO homolog called OlsD (BCAM2401). OlsD indeed hydroxylated

OL, but the hydroxylation did not occur on the ester-linked fatty acid. Surprisingly, Cyclopamine solubility dmso data obtained by mass spectrometry suggested that OlsD modifies the amide-linked fatty acid of OLs with a hydroxyl group (Fig. 2), a modification that was previously unknown. Unfortunately, their analysis did not allow for the determination of the exact position of the hydroxyl group. OlsD from B. cenocepacia is a 249-amino-acid protein, apparently lacking transmembrane helices (González-Silva et al., 2011). It is widely distributed within the genus Burkholderia, but homologs are also present in three Serratia strains. The gene coding for the 2-hydroxylase see more activity hydroxylating the ester-linked fatty acyl residue in the C-2 position in B. cenocepacia has not been identified yet. Rojas-Jiménez et al. (2005) had described the presence of four different OLs in R. tropici CIAT899. The presence of OlsC alone could not explain this number of distinct structures. Using a functional expression screen conjugating a cosmid bank from R. tropici into S. meliloti, Vences-Guzmán et al. (2011) identified the gene olsE coding for the hydroxylase OlsE. Mass spectrometry analysis showed that OlsE introduced a hydroxyl group in the ornithine moiety. So far,

the exact position of the hydroxylation could not be determined, but ninhydrin staining of the VAV2 different OLs shows that the hydroxyl group affects the reactivity of the lipid to ninhydrin. Bioinformatic predictions indicate that the OlsE protein (331 amino acids) from R. tropici CIAT899 is highly hydrophobic and might form between 4 and 6 transmembrane helices. OlsE belongs to the fatty acyl hydroxylase superfamily (cl01132), which is characterized by the presence of two copies of the HXHH motif. This superfamily includes fatty acid and carotene hydroxylases, sterol desaturases, and C-4 sterol methyl oxidase (Arthington et al., 1991; Bard et al., 1996; Mitchell & Martin, 1997; Kennedy et al., 2000). A similar motif can be found in membrane-bound fatty acid desaturases such as OLE1 from Saccharomyces cerevisiae and in bacterial alkane hydroxylase and xylene monooxygenase (Kok et al.