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Aeromonas are bacteria broadly spread in the environment, particularly in aquatic habitats and can induce human infections. Several virulence factors have been described associated with bacterial pathogenicity, such as the Type VI Secretion System (T6SS). This system translocates effector proteins into target cells through a bacteriophage-like contractile structure encoded by tss genes. Here, a total of 446 Aeromonas genome sequences were screened for T6SS and the proteins subjected to in silico analysis. The T6SS-encoding locus was detected in 243 genomes and its genes are encoded in a cluster containing 13 core and 5 accessory genes, in highly conserved synteny. The amino acid residues identity of T6SS proteins ranges from 78 to 98.8%. In most strains, a pair of tssD and tssI is located upstream the cluster (tssD-2, tssI-2) and another pair was detected distant from the cluster (tssD-1, tssI-1). Significant variability was seen in TssI (VgrG) C-terminal region, which was sorted in four groups based on its sequence length and protein domains. TssI containing ADP-ribosyltransferase domain are associated exclusively with TssI-1, while genes coding proteins carrying DUF4123 (a conserved domain of unknown function) were observed downstream tssI-1 or tssI-2 and escort of possible effector proteins. Genes coding proteins containing DUF1910 and DUF1911 domains were located only downstream tssI-2 and might represent a pair of toxin/immunity proteins. Nearly all strains display downstream tssI-3, that codes for a lysozyme family domain protein. These data reveal that Aeromonas T6SS cluster synteny is conserved and the low identity observed for some genes might be due to species heterogeneity or its niche/functionality. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s42770-020-00405-y.

There are many kinds of microorganisms in the gastrointestinal tract of mammals, some of which are closely related to the host. Rumen microorganisms are essential for normal physiological activities of their host by decomposing plant crude lignin and providing essential nutrients. The composition and diversity of this microbial population are influenced by the host, environment, and diet. Despite its importance, little is known about the effects of factors such as altitude variation on rumen microbial population abundance and diversity in different ruminants. Here, we described the changes in overall rumen bacteria in four groups of cattle, including the Zhongdian yellow cattle and Zhongdian yaks, grazing at high altitudes (3600 m); the Jiangcheng yellow cattle and Jiangcheng buffalo were kept at an altitude of 1100 m. We found that there was a significant difference in rumen bacterial abundance of the Zhongdian yellow cattle and Zhongdian yaks at high altitude and there was obvious homogeneity in rumen bacterial abundance and diversity in the Jiangcheng yellow cattle and Jiangcheng buffalo at low altitude. Therefore, our research concluded that under the same dietary environment, there were differences in the abundance and diversity of certain bacteria in the rumen of different breeds of cattle, indicating that host genetic factors and intestinal microorganisms related to altitudinal variation had a greater influence on rumen bacterial abundance in the cattle.

Bacteriocins are ribosomally synthesized antimicrobial peptides produced by prokaryotes. Here, the molecular characterization of aureocin 4181, a bacteriocin produced by Staphylococcus aureus 4181, a strain involved in bovine mastitis, is presented. Aureocin 4181 gene cluster (aurRID1CBAT) was mined from scaffold 15 of the draft genome of its producer strain. Three (AurABC) out of the four structural peptides of aureocin 4181 are identical to those of aureocin A70, except for AurD1 of aureocin 4181, which showed a conservative substitution of Leu(29) to Phe(29) when compared to AurD of aureocin A70. According to molecular mass determination and peptide sequencing, combined with genome sequencing data, aureocin 4181 is an N-formylated variant of aureocin A70. The analysis of its antimicrobial spectrum was extended to include strains of the two major contagious pathogens involved in bovine mastitis, S. aureus and Streptococcus agalactiae. Aureocin 4181 exhibited a striking activity against S. aureus, inhibiting most strains tested. Besides having a broader spectrum of activity, aureocin 4181 exhibited a stronger bacteriolytic action against the target strains and proved to be from two- to fourfold more active than aureocin A70 against S. aureus. Aureocin 4181 has potential to become an alternative drug for prevention and control of mastitic staphylococci, a pathogen that imposes a huge economic burden to dairy industry worldwide. It also represents the third four-component bacteriocin described in the literature, the second in staphylococci. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (10.1007/s42770-020-00315-z) contains supplementary material, which is available to authorized users.

Both Gram-positive and Gram-negative bacteria can take up exogenous DNA when they are in a competent state either naturally or artificially. However, the thick peptidoglycan layer in Gram-positive bacteria's cell wall is considered as a possible barrier to DNA uptake. In the present work, two transformation techniques have been evaluated in assessing the protocol's ability to introduce foreign DNA, pBBRGFP-45 plasmid which harbors kanamycin resistance and green fluorescent protein (GFP) genes into a Gram-positive bacterium, Bacillus cereus EB2. B. cereus EB2 is an endophytic bacterium, isolated from oil palm roots. A Gram-negative bacterium, Pseudomonas aeruginosa EB35 was used as a control sample for both transformation protocols. The cells were made competent using respective chemical treatment to Gram-positive and Gram-negative bacteria, and kanamycin concentration in the selective medium was also optimized. Preliminary findings using qualitative analysis of colony polymerase chain reaction (PCR)-GFP indicated that the putative positive transformants for B. cereus EB2 were acquired using the second transformation protocol. The positive transformants were then verified using molecular techniques such as observation of putative colonies on specific media under UV light, plasmid extraction, and validation analyses, followed by fluorescence microscopy. Conversely, both transformation protocols were relatively effective for introduction of plasmid DNA into P. aeruginosa EB35. Therefore, this finding demonstrated the potential of chemically prepared competent cells and the crucial step of heat-shock in foreign DNA transformation process of Gram-positive bacterium namely B. cereus was required for successful transformation.

Tobacco mosaic virus (TMV) coat protein (CP) self assembles in viral RNA deprived transgenic plants to form aggregates based on the physical conditions of the environment. Transgenic plants in which these aggregates are developed show resistance toward infection by TMV referred to as CP-MR. This phenomenon has been extensively used to protect transgenic plants against viral diseases. The mutants T42W and E50Q CP confer enhanced CP-MR as compared to the WT CP. The aggregates, when examined, show the presence of helical discs in the case of WT CP; on the other hand, mutants show the presence of highly stable non-helical long rods. These aggregates interfere with the accumulation of MP as well as with the disassembly of TMV in plant cells. Here, we explored an atomic level insight to the process of CP-MR through MD simulations. The subunit-subunit interactions were assessed with the help of MM-PBSA calculations. Moreover, classification of secondary structure elements of the protein also provided unambiguous information about the conformational changes occurring in the two chains, which indicated toward increased flexibility of the mutant protein and seconded the other results of simulations. Our finding indicates the essential structural changes caused by the mutation in CP subunits, which are critically responsible for CP-MR and provides an in silico insight into the effects of these transitions over CP-MR. These results could further be utilized to design TMV-CP-based small peptides that would be able to provide appropriate protection against TMV infection. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (10.1007/s42770-020-00225-0) contains supplementary material, which is available to authorized users.

Leifsonia xyli subsp. xyli (Lxx) colonizes the xylem vessels of sugarcane, a plant niche where microorganisms are highly exposed to oxidative and osmotic stresses. This study performed an in silico analysis of the genome of Lxx and characterized 16 genes related to the detoxification of oxidative species (peroxidases, O(2)(−) dismutases, and methionine reductases) and to the production and transport of osmolytes and analyzed their expression in vitro after 30, 60, and 120 min of exposure to H(2)O(2) or PEG. The PAGE activity of superoxide dismutase (Mn-SOD as confirmed by inhibition tests) and of catalase (CAT) and the accumulation of trehalose were also assessed. Exposure to H(2)O(2) increased the expression of most oxidative-responsive genes and decreased the expression of those related to osmotic responses, whereas the opposite occurred after exposure to PEG. The isoform profiles of CAT and Mn-SOD shifted in response to H(2)O(2) but not to PEG and Lxx cells accumulated more trehalose over time after exposure to PEG compared with non-exposed cells. The experimental results validated the in silico analysis and indicated that this obligate endophytic parasite has multiple and functional mechanisms to combat the stresses imposed by its host. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (10.1007/s42770-019-00163-6) contains supplementary material, which is available to authorized users.

Gemcitabine (GEM) is the drug used as first line to treat pancreatic cancer, one of the most devastating human tumors. This peculiar type of tumor develops resistance to several drugs, including GEM, due to its desmoplastic reaction and other features. The GEM chemoresistance has been investigated at molecular level aiming to find a pathway whose inhibition or activation should overcome it. Through next-generation sequencing was performed a chemogenomic assay of GEM using Saccharomyces cerevisiae as model cell and the results showed that more than 40% of genes related to GEM response in yeast possess unknown or dubious function. We choose two yeast mutants to individually validate the fitness defect results observed by chemogenomic assay, Δhmt1 and Δcsi1, and it was found that in addition to some already described pathways involved in GEM resistance, cells deficient in deneddylation enzyme Cop9 Signalosome Interactor 1 (Csi1p) presented a high sensitivity to GEM. This was confirmed by individual growth analyses of Δcsi1 cells exposed to GEM, and this phenotype was reverted with CSI1 complementation gene. Csi1p is a well-characterized homolog equivalent to human Csn6 subunit of COP9 signalosome (CSN) involved in deneddylation process. We highlighted too that epigenetic alterations, such as methylation mediated by protein arginine methyltransferase 1, play an important role in regulating gemcitabine treatment resistance. Our results point out new unexplored molecular pathways that can be used to overcome GEM resistance: the inhibition of CSN and the arginine methyltransferase activities. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (10.1007/s42770-019-00154-7) contains supplementary material, which is available to authorized users.

The wide use of antifungal agents has led to the development of resistance in the pathogenic yeast strain Candida albicans. Gain-of-function mutations in transcription factors such as Tac1p demonstrated their ability to control expression of the ABC transporter genes CDR1 and CDR2, and mediation of azole resistance. Previously, we obtained a series of azole-resistant isolates with high-level expression of CDR1 or/and CDR2, and identified the novel H741D mutation in Tac1p. In the present study, the TAC1 alleles from isolate C13 were introduced into tac1Δ/Δ mutant. The H741D change was seen in TAC1(C13) in addition to several other amino acid differences. Hyperactive alleles TAC1(C13) exhibited higher minimum inhibitory concentrations (MICs) of fluconazole and itraconazole than that observed in SN152 containing the wild-type TAC1 allele. And alleles TAC1(C13) conferred constitutively high levels of Cdr1p and Cdr2p. Moreover, the importance of H741D in conferring hyperactivity to TAC1 was also confirmed by site-directed mutagenesis. Compared with SN152, the presence of H741D resulted in > 2-fold increase in CDR1 and CDR2 gene and protein expression, > 4-fold increase in fluconazole and itraconazole MICs and higher rates of Rhodamine 6G efflux by 43.24%. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (10.1007/s42770-020-00336-8) contains supplementary material, which is available to authorized users.

High-risk human papillomaviruses (hr-HPVs) are the key risk factors implicated in the development of a significant proportion of head and neck squamous cell carcinomas (HNSCCs). We aimed to investigate the distribution of hr-HPV types and HPV16 lineages in a sample of patients with HNSCC and the possible association between HPV status and the expression of P16INK4A and NF-κB in Iranian HNSCC patients. We examined 108 formalin-fixed, paraffin-embedded (FFPE) histologically confirmed primary SCC tissue specimens of different head and neck anatomical sites. HPV types and HPV16 lineages were determined by nested PCR and overlapping nested PCR assays, respectively, followed by gene sequencing and phylogenetic analysis. The expression of p16INK4a and NF-κB was evaluated by immunohistochemistry. Twenty-five (23.1%) HNSCC tissue specimens were tested positive for HPV infection. The most prevalent HPV type was HPV-16, followed by HPV18 and HPV11. HPV16 variants belonged to the lineage A and lineage D which were further sorted into sublineages A1, A2, and D2. A significant association between HPV status and p16INK4a immunoreactivity was observed in more than 76% of the HPV-related HNSCCs (P

Shigella flexneri has been a major public health problem in developing countries. This work analyzed the frequency of 16 virulence genes, the genotypic diversity, and the antimicrobial resistance profiles of 130 S. flexneri strains isolated in Brazil. The ipaH gene was found in all the 130 strains. The frequencies of the other genes were variable ial (88.5%), sigA (82.3%), iuc (74.6%), virA (73%), pic (72.3%), virF (57.7%), sat (48.5%), ipaBCD (37%), sen (36%), set1A (35.4%), sepA (30%), set1B (30%), virB (14%), icsA (10%), and ipgD (5.4%). A total of 57 (43.8%) strains were multidrug-resistant. ERIC-PCR grouped 96 of the strains into a single cluster with ≥ 70.4% of similarity, 75 of these strains presented a similarity ≥ 80.9%. PFGE grouped 120 of the strains into a single cluster with 57.4% of similarity and 82 of these strains presented a similarity ≥ 70.6%. In conclusion, the high frequency of some virulence genes reinforces the pathogenic potential of the strains studied. The high rates of MDR strains are alarming once it may lead to failure when antimicrobial treatment is necessary. Genotype techniques reveled a major cluster with high genetic similarity including S. flexneri strains from the different Brazilian states and distinct years of isolation, showing that they probably emerged from a common ancestor. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (10.1007/s42770-020-00332-y) contains supplementary material, which is available to authorized users.

This study compared the ability of pulsed-field gel electrophoresis (PFGE), flaA small variable region (SVR) sequencing, analysis of the clustered regularly interspaced short palindromic repeats locus by high resolution melting analysis (CRISPR-HRMA), and multilocus sequence typing (MLST) for typing 111 Campylobacter jejuni strains isolated from diverse sources during 20 years in Brazil. For this, we used previous results obtained by PFGE and flaA-SVR sequencing from our research group and performed CRISPR-HRMA and MLST typing for the first time. Furthermore, the discrimination index (DI) of each method was accessed. The DI for PFGE, flaA-SVR sequencing, CRISPR-HRMA, and MLST was 0.980, 0.932, 0.868, and 0.931, respectively. By PFGE and flaA-SVR sequencing, some strains from clinical and non-clinical sources and from humans and animals presented ≥ 80% similarity. Similarly, some strains from different origins presented the same ST and CRISPR-HRMA types. In conclusion, despite the different DI values, all assays provided the same epidemiological information suggesting that a potential transmission may have occurred between C. jejuni from clinical and non-clinical sources and from animals and humans in Brazil. Furthermore it was demonstrated the suitability of PFGE that should be used preferably together with MLST and/or flaA-SVR sequencing for typing C. jejuni strains.

Salmonella Dublin is a strongly adapted serovar that causes enteritis and/or systemic disease with high rates of mortality in cattle and occasionally infects humans. Despite the importance of this serovar, there is a lack of studies in Brazil. The aim of this study was to characterize the genetic diversity of 112 S. Dublin strains isolated from humans and animals in Brazil by CRISPR and CRISPR-MVLST and the relatedness among strains by MLST. In addition, the frequency of some important virulence genes was verified. The strains studied belonged to nine different sequence types, being all of them single- or double-locus variants of the ST10. CRISPR discriminated the strains into 69 subtypes with a similarity ≥ 84.4% and CRISPR-MVLST into 72 subtypes with a similarity ≥ 84.7%. The virulence genes ratB, lpfA, mgtC, avrA, sopB, sopE2, sifA, sseA, ssrA, csgA, fliC, and sinH were found in all the strains studied, while spvB, spvC, sodCl, rpoS, sipA, sipD, invA, and hilA were detected in ≥ 93.7% of the strains. In conclusion, the high similarity among the strains reinforces the clonal nature of the strains of this serovar that may have descended from a common ancestor that little differed over 33 years in Brazil. CRISPR and CRISPR-MVLST showed to be good alternatives to type S. Dublin strains. MLST suggested that S. Dublin strains from Brazil were phylogenetically related to strains from other parts of the globe. Moreover, the high frequency of virulence genes among the strains studied reinforces the capacity of S. Dublin to cause invasive diseases. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (10.1007/s42770-019-00156-5) contains supplementary material, which is available to authorized users.

The Xanthomonadaceae family comprises the genera Xanthomonas and Xylella, which include plant pathogenic species that affect economically important crops. The family also includes the plant growth-promoting bacteria Pseudomonas geniculata and Stenotrophomonas rhizophila, and some other species with biotechnological, medical, and environmental relevance. Previous work identified molecular signatures that helped to understand the evolutionary placement of this family within gamma-proteobacteria. In the present study, we investigated whether insertions identified in highly conserved proteins may also be used as molecular markers for taxonomic classification and identification of members within the Xanthomonadaceae family. Four housekeeping proteins (DNA repair and replication-related and protein translation enzymes) were selected. The insertions allowed discriminating phytopathogenic and plant growth-promoting groups within this family, and also amino acid sequences of these insertions allowed distinguishing different genera and, eventually, species as well as pathovars. Moreover, insertions in the proteins MutS and DNA polymerase III (subunit alpha) are conserved in Xylella fastidiosa, but signatures in DNA ligase NAD-dependent and Valyl tRNA synthetase distinguish particular subspecies within the genus. The genus Stenotrophomonas and Pseudomonas geniculata could be distinguishable based on the insertions in MutS, DNA polymerase III (subunit alpha), and Valyl tRNA synthetase, although insertion in DNA ligase NAD-dependent discriminates these bacteria at the species level. All these insertions differentiate species and pathovars within Xanthomonas. Thus, the insertions presented support evolutionary demarcation within Xanthomonadaceae and provide tools for the fast identification in the field of these bacteria with agricultural, environmental, and economic relevance.

Salmonella Typhimurium sequence type 313 (S. Typhimurium ST313) has caused invasive disease mainly in sub-Saharan Africa. In Brazil, ST313 strains have been recently described, and there is a lack of studies that assessed by whole genome sequencing (WGS)—the relationship of these strains. The aims of this work were to study the phylogenetic relationship of 70 S. Typhimurium genomes comparing strains of ST313 (n = 9) isolated from humans and food in Brazil among themselves, with other STs isolated in this country (n = 31) and in other parts of the globe (n = 30) by 16S rRNA sequences, the Gegenees software, whole genome multilocus sequence typing (wgMLST), and average nucleotide identity (ANI) for the genomes of ST313. Additionally, pangenome analysis was performed to verify the heterogeneity of these genomes. The phylogenetic analyses showed that the ST313 genomes were very similar among themselves. However, the ST313 genomes were usually clustered more distantly to other STs of strains isolated in Brazil and in other parts of the world. By pangenome calculation, the core genome was 2,880 CDSs and 4,171 CDSs singletons for all the 70 S. Typhimurium genomes studied. Considering the 10 ST313 genomes analyzed the core genome was 4,112 CDSs and 76 CDSs singletons. In conclusion, the ST313 genomes from Brazil showed a high similarity among them which information might eventually help in the development of vaccines and antibiotics. The pangenome analysis showed that the S. Typhimurium genomes studied presented an open pangenome, but specifically tending to become close for the ST313 strains. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (10.1007/s42770-019-00155-6) contains supplementary material, which is available to authorized users.

Armillaria species (Basidiomycota, Physalacriaceae) are well known as plant pathogens related to serious root rot disease on various trees in forests and plantations. Interestingly, some Armillaria species are essential symbionts of the rare Chinese medicinal herb Gastrodia elata, a rootless and leafless orchid used for over 2000 years. In this work, an 87.3-M draft genome of Armillaria gallica 012m strain, which was symbiotic with G. elata, was assembled. The genome includes approximately 23.6% repetitive sequences and encodes 26,261 predicted genes. In comparison with other four genomes of Armillaria, the following gene families related to pathogenicity/saprophytic phase, including cytochrome P450 monooxygenases, carbohydrate-active enzyme AA3, and hydrophobins, were significantly contracted in A. gallica 012m. These characteristics may be beneficial for G. elata to get less injuries. The genome-guided analysis of differential expression between rhizomorph (RH) and vegetative mycelium (VM) showed that a total of 2549 genes were differentially expressed, including 632 downregulated genes and 1917 upregulated genes. In the RH, most differentially expressed genes (DEGs) related to pathogenicity were significantly upregulated. To further elucidate gene function, Gene Ontology enrichment analysis showed that the upregulated DEGs significantly grouped into monooxygenase activity, hydrolase activity, glucosidase activity, extracellular region, fungal cell wall, response to xenobiotic stimulus, response to toxic substance, etc. These phenomena indicate that RH had better infection ability than VM. The infection ability of RH may be beneficial for G. elata to obtain nutrition, because the rhizomorph constantly infected the nutritional stems of G. elata and formed the hyphae that can be digested by G. elata. These results clarified the characteristics of A. gallica 012m and the reason why the strain 012m can establish a symbiotic relationship with G. elata in some extent from the perspective of genomics. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (10.1007/s42770-020-00317-x) contains supplementary material, which is available to authorized users.

Aeromonas dhakensis is an emergent human pathogen with medical importance. This study was aimed to determine the sequence types (STs), genetic diversity, and phylogenetic relationships of different clinical sources of 47 A. dhakensis from Malaysia using multilocus sequence typing (MLST), goeBURST, and phylogenetic analyses. The analysis of a concatenated six-gene tree with a nucleotide length of 2994 bp based on six housekeeping genes (gyrB, groL, gltA, metG, ppsA, and recA) and independent analyses of single gene fragments was performed. MLST was able to group 47 A. dhakensis from our collection into 36 STs in which 34 STs are novel STs. The most abundant ST521 consisted of five strains from peritoneal fluid and two strains from stools. Comparison of 62 global A. dhakensis was carried out via goeBURST; 94.4% (34/36) of the identified STs are novel and unique in Malaysia. Two STs (111 and 541) were grouped into clonal complexes among our strains and 32 STs occurred as singletons. Single-gene phylogenetic trees showed varying topologies; groL and rpoD grouped all A. dhakensis into a tight-cluster with bootstrap values of 100% and 99%, respectively. A poor phylogenetic resolution encountered in single-gene analyses was buffered by the multilocus phylogenetic tree that offered high discriminatory power (bootstrap value = 100%) in resolving all A. dhakensis from A. hydrophila and delineating the relationship among other taxa. Genetic diversity analysis showed groL as the most conserved gene and ppsA as the most variable gene. This study revealed novel STs and high genetic diversity among clinical A. dhakensis from Malaysia. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (10.1007/s42770-020-00239-8) contains supplementary material, which is available to authorized users.

Aeromonas are bacteria widely distributed in the environment, and some species are able to cause infections in humans, of which diarrhea is the most common. The objective of this study was to evaluate the presence of virulence and antimicrobial resistance associated characteristics in A. veronii biovar sobria strain 312M isolated from diarrheal stools. For this, the genome sequencing and phenotypical tests were performed. The draft genome annotation revealed several complete pathways associated with carbon metabolism and a mucin-desulfating sulfatase which may contribute to intestine colonization, and a large number of virulence-associated genes encoding structures associated with adhesion, toxins, and secretion systems. The strain exhibited swimming and swarming motility, biofilm formation, and hemolytic activity. It was resistant to ampicillin, ampicillin/sulbactam, and amoxicillin-clavulanic acid. Although a cphA gene encoding a narrow-spectrum carbapenase was identified in the strain genome, no carbapenemase activity was detected in the antimicrobial susceptibility test. When compared with other A. veronii with complete genomes, the main differences in virulence characteristics are related to lateral flagella and type III and VI secretion systems; the antimicrobial resistance spectrum also varied among strains. The results indicated that A. veronii biovar sobria 312M presents high virulence potential and resistance to limited classes of antimicrobials.

Zymomonas mobilis is a bacterium of industrial interest due to its high ethanol productivity and high tolerance to stresses. Although the physiological parameters of fermentation are well characterized, there are few studies on the molecular mechanisms that regulate the response to fermentative stress. Z. mobilis ZM4 presents five different sigma factors identified in the genome annotation, but the absence of sigma 38 leads to the questioning of which sigma factors are responsible for its mechanism of fermentative stress response. Thus, in this study, factors sigma 32 and sigma 24, traditionally related to heat shock, were tested for their influence on the response to osmotic and ethanol stress. The overexpression of these sigma factors in Z. mobilis ZM4 strain confirmed that both are associated with heat shock response, as described in other bacteria. Moreover, sigma 32 has also a role in the adaptation to osmotic stress, increasing both growth rate and glucose influx rate. The same strain that overexpresses sigma 32 also showed a decrease in ethanol tolerance, suggesting an antagonism between these two mechanisms. It was not possible to conclude if sigma 24 really affects ethanol tolerance in Z. mobilis, but the overexpression of this sigma factor led to a decrease in ethanol productivity.

The objective of this study was to determine the frequency and seasonal distributions of HBoV detections among Iranian children presenting with acute respiratory or gastrointestinal symptoms and to compare infections among children with concomitant respiratory syncytial virus (RSV) and rotavirus (RV) infections. A cross-sectional study at Mofid Children’s Hospital in Tehran, Iran, enrolled children

JC polyomavirus (JCPyV) is the causative agent for progressive multifocal leukoencephalopathy (PML) in immunocompromised patients. More than 40% of healthy population excretes JCPyV particles in their urine. As JCPyV is ubiquitous in human, the definition of genotype distribution can help trace population migration. In this study, to define the frequency of JCPyV in southwest of Iran, urine samples of 161 volunteers including 80 healthy individuals and 81 HIV-infected patients were collected. PCR assays and sequence analysis were performed using JCPyV-specific primers designed against VP1 coding region. JCPyV DNA was detected in 65 out of 81 urine samples (80.2%) of HIV-infected, and in 43 out of 80 urine samples (53.8%) of healthy individuals (P = 0.001). The shedding of JCPyV among HIV-infected patients revealed an age-related pattern while such relationship was not observed in healthy individuals group. The most common genotype found in this region was genotype 3A (80.8%), followed by genotype 2D (11.5%), 4 (3.8%), and 7 (3.8%). The frequency of JCPyV in the urine of HIV-infected patients was found significantly higher than in the healthy individuals (P = 0.001).