Composition and metabolic flexibility of hydrocarbon-degrading consortia in oil reservoirs.

Hydrocarbon-degrading consortia (HDC) play an important role in petroleum exploitation. However, the real composition and metabolic mechanism of HDC in the microbial enhanced oil recovery (MEOR) process remain unclear. By combining 13C-DNA stable isotope probing microcosms with metagenomics, some newly reported phyla, including Chloroflexi, Synergistetes, Thermotogae, and Planctomycetes, dominated the HDC in the oil reservoirs. In the field trials, the HDC in the aerobic-facultative-anaerobic stage of oilfields jointly promoted the MEOR process, with monthly oil increments of up to 189 tons. Pseudomonas can improve oil recovery by producing rhamnolipid in the facultative condition. Roseovarius was the novel taxa potentially oxidizing alkane and producing acetate to improve oil porosity and permeability in the aerobic condition. Ca. Bacteroidia were the new members potentially degrading hydrocarbons by fumarate addition in the anaerobic environment. Comprehensive identification of the active HDC in oil reservoirs provides a novel theoretical basis for oilfield regulatory scheme.

Disparities in medical recommendations from AI-based chatbots across different countries/regions.

This study explores disparities and opportunities in healthcare information provided by AI chatbots. We focused on recommendations for adjuvant therapy in endometrial cancer, analyzing responses across four regions (Indonesia, Nigeria, Taiwan, USA) and three platforms (Bard, Bing, ChatGPT-3.5). Utilizing previously published cases, we asked identical questions to chatbots from each location within a 24-h window. Responses were evaluated in a double-blinded manner on relevance, clarity, depth, focus, and coherence by ten experts in endometrial cancer. Our analysis revealed significant variations across different countries/regions (p < 0.001). Interestingly, Bing's responses in Nigeria consistently outperformed others (p < 0.05), excelling in all evaluation criteria (p < 0.001). Bard also performed better in Nigeria compared to other regions (p < 0.05), consistently surpassing them across all categories (p < 0.001, with relevance reaching p < 0.01). Notably, Bard's overall scores were significantly higher than those of ChatGPT-3.5 and Bing in all locations (p < 0.001). These findings highlight disparities and opportunities in the quality of AI-powered healthcare information based on user location and platform. This emphasizes the necessity for more research and development to guarantee equal access to trustworthy medical information through AI technologies.

Menopausal hormone therapy decreases the likelihood of diabetes development in peri­menopausal individuals with prediabetes.

BACKGROUND: The influence of menopausal hormone therapy (MHT) on the probability of developing diabetes mellitus in individuals with prediabetes remains uncertain. METHODS: This retrospective cohort study, utilizing the TriNetX U.S. Collaborative Network, investigated cohorts, implemented propensity score matching, and analyzed outcomes associated with diabetes mellitus. The study focused on individuals aged 46-60 with prediabetes prior to menopause, categorizing them into MHT and non-MHT groups. Further stratified analyses, including variables such as age and race, were conducted to thoroughly examine potential variations in outcomes. RESULTS: The study involved 6566 individuals (MHT and non-MHT), with propensity score matching ensuring balanced cohorts. Over a 20-year follow-up, the MHT group demonstrated a lower incidence of diabetes mellitus compared to the non- MHT group, with a Hazard Ratio of 0.693 (95 % CI: 0.577, 0.832). Stratified analyses revealed age-specific nuances, with significant protective effects in individuals aged 46-50 and 55-60. Additionally, ethnicity played a role, with MHT demonstrating significant benefits in White individuals but not in the Black or Asian populations. BMI analysis indicated a significant risk reduction with MHT in individuals with BMI less than or equal to 24.9 and 25-29.9 kg/m 2, but not in those with BMI greater than or equal to 30 kg/m 2. CONCLUSION: In our study, we demonstrate a sustained 20-year decrease in the risk of diabetes among premenopausal individuals with prediabetes who undergo menopausal hormone therapy.

Comparative genomic analyses of Cutibacterium granulosum provide insights into genomic diversity.

Cutibacterium granulosum, a commensal bacterium found on human skin, formerly known as Propionibacterium granulosum, rarely causes infections and is generally considered non-pathogenic. Recent research has revealed the transferability of the multidrug-resistant plasmid pTZC1 between C. granulosum and Cutibacterium acnes, the latter being an opportunistic pathogen in surgical site infections. However, there is a noticeable lack of research on the genome of C. granulosum, and the genetic landscape of this species remains largely uncharted. We investigated the genomic features and evolutionary structure of C. granulosum by analyzing a total of 30 Metagenome-Assembled Genomes (MAGs) and isolate genomes retrieved from public databases, as well as those generated in this study. A pan-genome of 6,077 genes was identified for C. granulosum. Remarkably, the 'cloud genes' constituted 62.38% of the pan-genome. Genes associated with mobilome: prophages, transposons [X], defense mechanisms [V] and replication, recombination and repair [L] were enriched in the cloud genome. Phylogenomic analysis revealed two distinct mono-clades, highlighting the genomic diversity of C. granulosum. The genomic diversity was further confirmed by the distribution of Average Nucleotide Identity (ANI) values. The functional profiles analysis of C. granulosum unveiled a wide range of potential Antibiotic Resistance Genes (ARGs) and virulence factors, suggesting its potential tolerance to various environmental challenges. Subtype I-E of the CRISPR-Cas system was the most abundant in these genomes, a feature also detected in C. acnes genomes. Given the widespread distribution of C. granulosum strains within skin microbiome, our findings make a substantial contribution to our broader understanding of the genetic diversity, which may open new avenues for investigating the mechanisms and treatment of conditions such as acne vulgaris.

Modified endoluminal ureteral stenting for the management of proximal ureteral obstruction in two cats.

Case series summary: Two cases of placement of modified endoluminal ureteral stents are described, for revision of a subcutaneous ureteral bypass (SUB) and for primary treatment of obstructive ureterolithiasis. Modified endoluminal stents were inserted through the ureterotomy, anchored in the renal pelvis with a single pigtail and shortened to a length sufficient to span the proximal ureter and ureterotomy site. Relevance and novel information: The advantages of this approach as a surgical option for feline obstructive ureterolithiasis are demonstrated, including the avoidance of disruption, or bypass, of the ureterovesicular junction, minimisation of implanted foreign material and avoidance of intravesicular stent mass, maintenance of the physiological route of urine flow, including preservation of active distal ureteral function, and limitation of the potential complications of ureterotomy. The clinical efficacy of this adaptation of the previously published endoluminal stenting technique is demonstrated with its applicability de novo and in the revision of other stenting procedures.

HMDB: A curated database of genes involved in hydrocarbon monooxygenation reaction with homologous genes as background.

The investigation of hydrocarbon degradation potential of environmental microorganisms is an important research topic, whether for the global carbon cycle or oil pollution remediation. Under aerobic conditions, the microorganisms employ a range of monooxygenases to use hydrocarbons substrates as a source of carbon and energy. With the explosion of sequencing data, mining genes in genomes or metagenomes has become computationally expensive and time-consuming. We proposed the HMDB, which is a professional gene database of hydrocarbon monooxygenases. HMDB contains 38 genes, which encode 11 monooxygenases responsible for the hydroxylation of 8 hydrocarbons. To reduce false positives, the strategy of using homologous genes as background noise was applied for HMDB. We added 10,095 gene sequences of homologous enzymes which took non-hydrocarbons as substrates to HMDB. The classic BLAST method and best-hit strategy were recommended for HMDB usage, but not limited. The performance of HMDB was validated using 264,402 prokaryote genomes from RefSeq and 51 metagenomes from SRA. The results showed that HMDB database had high sensitivity and low false positive rate. We release the HMDB database here, hoping to speed up the process for investigation of hydrocarbon monooxygenases in massive metagenomic data. HMDB is freely available at http://www.orgene.net/HMDB/.

Roles of adenine methylation in the physiology of Lacticaseibacillus paracasei.

Lacticaseibacillus paracasei is an economically important bacterial species, used in the food industry and as a probiotic. Here, we investigate the roles of N6-methyladenine (6mA) modification in L. paracasei using multi-omics and high-throughput chromosome conformation capture (Hi-C) analyses. The distribution of 6mA-modified sites varies across the genomes of 28 strains, and appears to be enriched near genes involved in carbohydrate metabolism. A pglX mutant, defective in 6mA modification, shows transcriptomic alterations but only modest changes in growth and genomic spatial organization.

Modulus-Modulated All-Organic Core-Shell Nanofiber with Remarkable Piezoelectricity for Energy Harvesting and Condition Monitoring.

The low piezoelectricity of piezoelectric polymers significantly restricts their applications. Introducing inorganic fillers can slightly improve the piezoelectricity of polymers, whereas it is usually at the cost of flexibility and durability. In this work, using a modulus-modulated core-shell structure strategy, all-organic nanofibers with remarkable piezoelectricity were designed and prepared by a coaxial electrospinning method. It was surprisingly found that the introduction of a nonpiezoelectric polymeric core (e.g., polycarbonate, PC) can result in 110% piezoelectric coefficient (d33) enhancement in a poly(vinylidenefluoride-co-trifluoroethylene) (PVDF-TrFE) nanofiber. Accordingly, the all-organic PVDF-TrFE@PC core-shell nanofiber exhibits record-high energy-harvesting performance (i.e., 126 V output voltage, 710 mW m-2 power density) among the reported organic piezoelectric materials. In addition, the excellent sensing capability of the core-shell nanofiber enabled us to develop a wireless vibration monitoring and analyzing system, which realizes the real-time vibration detection of a power transformer.

Placental mesenchymal dysplasia complicated with sudden fetal demise and amniotic fluid embolism: a case report.

BACKGROUND: Placenta mesenchymal dysplasia (PMD) is a rare placental anomaly associated with various fetal and maternal complications. Whether close ultrasound surveillance can prevent intrauterine fetal demise (IUFD) in patients with PMD is still under investigation. Amniotic fluid embolism (AFE) is a rare, lethal, and unpredictable maternal complication that has never been described in association with PMD. Here, we report a case of PMD, in which the fetus eventually demised in utero despite weekly color Doppler monitoring, and the mother subsequently encountered AFE during delivery. CASE PRESENTATION: A 43-year-old woman who had received three frozen embryo transfer, was found to have a singleton pregnancy with an enlarged multi-cystic placenta at 8 weeks' gestation. Fetal growth restriction (FGR) was noted since the 21stweek. The fetus eventually demised in-utero at 25 weeks despite weekly color Doppler surveillance. Cesarean section was performed under general anesthesia due to placenta previa totalis and antepartum hemorrhage. During surgery, the patient experienced a sudden blood pressure drop and desaturation followed by profound coagulopathy. AFE was suspected. After administration of inotropic agents and massive blood transfusion, the patient eventually survived AFE. PMD was confirmed after pathological examination of the placenta. CONCLUSIONS: While FGR can be monitored by color Doppler, our case echoed previous reports that IUFD may be unpreventable even under intensive surveillance in PMD cases. Although AFE is usually considered unpredictable, PMD can result in cumulative risk factors contributing to AFE. Whether a specific link exists between the pathophysiology of PMD and AFE requires further investigation.

Tailoring the Electrical Energy Storage Capability of Dielectric Polymer Nanocomposites via Engineering of the Host-Guest Interface by Phosphonic Acids.

Polymer nanocomposites have attracted broad attention in the area of dielectric and energy storage. However, the electrical and chemical performance mismatch between inorganic nanoparticles and polymer leads to interfacial incompatibility. In this study, phosphonic acid molecules with different functional ligands were introduced to the surface of BaTiO3 (BT) nanoparticles to tune their surface properties and tailor the host-guest interaction between BT and poly(vinylideneflyoride-co-hexafluroro propylene) (P(VDF-HFP)). The dielectric properties and electrical energy storage capability of the nanocomposites were recorded by broadband dielectric spectroscopy and electric displacement measurements, respectively. The influence of the ligand length and polarity on the dielectric properties and electrical energy storage of the nanocomposites was documented. The nanocomposite with 5 vol% 2,3,4,5,6-pentafluorobenzyl phosphonic acid (PFBPA)-modified BT had the highest energy density of 12.8 J cm-3 at 400 MV m-1, i.e., a 187% enhancement in the electrical energy storage capability over the pure P(VDF-HFP). This enhancement can be attributed to the strong electron-withdrawing effect of the pentafluorobenzyl group of PFBPA, which changed the electronic nature of the polymer-particle interface. On the other hand, PFBPA improves the compatibility of the host-guest interface in the nanocomposites and decreases the electrical mismatch of the interface. These results provide new insights into the design and preparation of high-performance dielectric nanocomposites.

A novel alkane monooxygenase (alkB) clade revealed by massive genomic survey and its dissemination association with IS elements.

Background: Alkanes are important components of fossil energy, such as crude oil. The alkane monooxygenase encoded by alkB gene performs the initial step of alkane degradation under aerobic conditions. The alkB gene is well studied due to its ubiquity as well as the availability of experimentally functional evidence. The alkBFGHJKL and alkST clusters are special kind of alkB-type alkane hydroxylase system, which encode all proteins necessary for converting alkanes into corresponding fatty acids. Methods: To explore whether the alkBFGHJKL and alkST clusters were widely distributed, we performed a large-scale analysis of isolate and metagenome assembled genome data (>390,000 genomes) to identify these clusters, together with distributions of corresponding taxonomy and niches. The set of alk-genes (including but not limited to alkBGHJ) located near each other on a DNA sequence was defined as an alk-gene cluster in this study. The alkB genes with alkGHJ located nearby on a DNA sequence were picked up for the investigation of putative alk-clusters. Results: A total of 120 alk-gene clusters were found in 117 genomes. All the 117 genomes are from strains located only in α- and γ-proteobacteria. The alkB genes located in alk-gene sets were clustered into a deeply branched mono-clade. Further analysis showed similarity organization types of alk-genes were observed within closely related species. Although a large number of IS elements were observed nearby, they did not lead to the wide spread of the alk-gene cluster. The uneven distribution of these elements indicated that there might be other factors affecting the transmission of alk-gene clusters. Conclusions: We conducted systematic bioinformatics research on alk-genes located near each other on a DNA sequence. This benchmark dataset of alk-genes can provide base line for exploring its evolutional and ecological importance in future studies.

Outcomes of "sandwich" chemoradiotherapy compared with chemotherapy alone for the adjuvant treatment of FIGO stage III endometrial cancer.

Objective: To analyze and compare outcomes of adjuvant chemoradiotherapy in patients with International Federation of Gynecology and Obstetrics (FIGO) stage III endometrial cancer (EC) patients using the "Sandwich" sequence and chemotherapy (CT) alone. Methods: From, 2005 to, 2019, we retrospectively reviewed 80 patients with FIGO stage III EC who received treatment at our institute. We analyzed 66 patients who had undergone complete surgical staging followed by adjuvant treatment with sandwich chemoradiotherapy (39 patients) and CT alone (27 patients). The 5-year overall survival (OS), progression-free survival (PFS), and disease-specific survival (DSS) were calculated using the Kaplan-Meier method. Additional prognostic factors were analyzed using Cox proportional hazards regression. Results: Herein, the analysis was conducted using 66 patients with a median follow-up period of 50 and 85 months in the sandwich and CT-alone arms. Comparing the sandwich sequence and CT-alone groups, the 5-year OS and PFS were 87% vs. 70% (p = 0.097) and 77% vs. 65% (p = 0.209), respectively. The sandwich therapy conferred an improved 5-year DSS (92% vs. 70%, p = 0.041) and a lower local recurrence rate (0% vs. 11%, p = 0.031). In multivariable analyses, grade 3 histology and deep myometrial invasion were independent risk factors for 5-year OS and DSS. The sandwich sequence was a positive predictor for 5-year DSS (hazard ratio [HR] = 0.23, p = 0.029). The sandwich arm demonstrated higher acute hematologic toxicity than the CT-alone arm. CT dose delay/reduction and treatment completion rates were similar in both groups. Conclusion: For patients with stage III EC, postoperative sandwich chemoradiotherapy appears to offer a superior 5-year DSS and local control with tolerable toxicity when compared with CT alone.

Complete Genome Sequences of One Salt-Tolerant and Petroleum Hydrocarbon-Emulsifying Terribacillus saccharophilus Strain ZY-1.

Salt tolerance is one of the most important problems in the field of environmental governance and restoration. Among the various sources of factors, except temperature, salinity is a key factor that interrupts bacterial growth significantly. In this regard, constant efforts are made for the development of salt-tolerant strains, but few strains with salt tolerance, such as Terribacillus saccharophilus, were found, and there are still few relevant reports about their salt tolerance from complete genomic analysis. Furthermore, with the development of the economy, environmental pollution caused by oil exploitation has attracted much attention, so it is crucial to find the bacteria from T. saccharophilus which could degrade petroleum hydrocarbon even under high-salt conditions. Herein, one T. saccharophilus strain named ZY-1 with salt tolerance was isolated by increasing the salinity on LB medium step by step with reservoir water as the bacterial source. Its complete genome was sequenced, which was the first report of the complete genome for T. saccharophilus species with petroleum hydrocarbon degradation and emulsifying properties. In addition, its genome sequences were compared with the other five strains that are from the same genus level. The results indicated that there really exist some differences among them. In addition, some characteristics were studied. The salt-tolerant strain ZY-1 developed in this study and its emulsification and degradation performance of petroleum hydrocarbons were studied, which is expected to widely broaden the research scope of petroleum hydrocarbon-degrading bacteria in the oil field environment even in the extreme environment. The experiments verified that ZY-1 could significantly grow not only in the salt field but also in the oil field environment. It also demonstrated that the developed salt-tolerant strain can be applied in the petroleum hydrocarbon pollution field for bioremediation. In addition, we expect that the identified variants which occurred specifically in the high-salt strain will enhance the molecular biological understanding and be broadly applied to the biological engineering field.

Case Report: Myomatous erythrocytosis syndrome presenting as rapid growth of an extra-uterine mass.

Objective: To report a case of myomatous erythrocytosis syndrome (MES) with an extra-uterine manifestation. Case report: A 43-year-old woman presented with progressive abdominal distension and rapid enlargement of a pelvic mass. Upon survey, a high-level of hemoglobin (19.0 g/dl) was documented. The initial impression was an ovarian malignancy, but uterine sarcoma could not be ruled out because of its rapid growth. However, during exploratory laparotomy, the pelvic mass was found to be a 31 cm broad ligament leiomyoma; which is extremely rare for its size and location. The specimen was further studied immunohistochemically, which revealed excessive expressions of erythropoietin and erythropoietin receptors in addition to the diffusely matured blood vessels in the myoma tissue. The patient's hemoglobin level resumed to normal three months post-surgery. The diagnosis of MES was confirmed both clinically and histologically. Conclusion: A correct preoperative diagnosis is challenging when MES manifests as an extrauterine mass. The coexistence of MES should be considered in the management of all leiomyoma with polycythemia, regardless of locations.

CnnPOGTP: a novel CNN-based predictor for identifying the optimal growth temperatures of prokaryotes using only genomic k-mers distribution.

SUMMARY: Temperature is very important for the growth of microorganisms. Appropriate temperature conditions can improve the possibility for isolation of currently uncultured microorganisms. The development of metagenomic binning technology had dramatically increased the availability of genomic information of prokaryotes, providing convenience to infer the optimal growth temperature (OGT). Here, we proposed CnnPOGTP, a predictor for OGTs of prokaryotes based on deep learning method using only k-mers distribution derived from genomic sequence. This method was annotation free, and the predicted OGT could be obtained by simply providing the genome sequence to the CnnPOGTP website. AVAILABILITY AND IMPLEMENTATION: http://www.orgene.net/CnnPOGTP. SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.

Comparative genomic analysis of 455 Lactiplantibacillus plantarum isolates: Habitat-specific genomes shaped by frequent recombination.

A large-scale comparative genomic analysis together with genome-wide association study of 455 Lactiplantibacillus (L.) plantarum genomes was performed. Firstly, the study generated phylogenic tree using core-genome of L. plantarum, and the phylogenetic tree comprised two major clades. The isolates in clade B were genetically more diverse than those of clade A. Furthermore, a mono-clade (clade B1) of 12 isolates was identified within clade B in L. plantarum. It is interesting to note that these 12 isolates were originated from diverse niches and wide geographic regions. Plant-associated isolates were distributed evenly across the phylogenetic tree. In contrast, more dairy product-originated isolates were distributed in clade B, while the animal- and meat product-originated isolates located mainly in clade A. The overall r/m ratio (ratio of recombination and mutation events) of all 455 L. plantarum isolates (1.181) was a lot lower than that of clade B1 (5.510), and there was a seven-fold difference in the r/m ratio between animal-originated isolates distributed to clade A (0.607) and clade B (4.373). The dairy and animal-originated isolates possessed multiple environment-specific genes. Our findings deepen the understanding of the niche-specific genome diversity of L. plantarum.

Reclassification of Enterobacter sp. FY-07 as Kosakonia oryzendophytica FY-07 and Its Potential to Promote Plant Growth.

Precise classification of bacteria facilitates prediction of their ecological niche. The genus Enterobacter includes pathogens of plants and animals but also beneficial bacteria that may require reclassification. Here, we propose reclassification of Enterobacter FY-07 (FY-07), a strain that has many plant-growth-promoting traits and produces bacterial cellulose (BC), to the Kosakonia genera. To re-examine the taxonomic position of FY-07, a polyphasic approach including 16S rRNA gene sequence analysis, ATP synthase ß subunit (atpD) gene sequence analysis, DNA gyrase (gyrB) gene sequence analysis, initiation translation factor 2 (infB) gene sequence analysis, RNA polymerase ß subunit (rpoB) gene sequence analysis, determination of DNA G + C content, average nucleotide identity based on BLAST, in silico DNA-DNA hybridization and analysis of phenotypic features was applied. This polyphasic analysis suggested that Enterobacter sp. FY-07 should be reclassified as Kosakonia oryzendophytica FY-07. In addition, the potential of FY-07 to promote plant growth was also investigated by detecting related traits and the colonization of FY-07 in rice roots.

Deep mining decreases the microbial taxonomic and functional diversity of subsurface oil reservoirs.

Microbes in subsurface oil reservoirs play important roles in elemental cycles and biogeochemical processes. However, the community assembly pattern of indigenous microbiome and their succession under long-term human activity remain poorly understood. Here we studied the microbial community assembly in underground sandstone cores from 190 to 2050 m in northeast China and their response to long-term oil recovery (10-50 years). Indigenous microbiome in subsurface petroleum reservoirs were dominated by Gammaproteobacteria, Firmicutes, Alphaproteobacteria, Bacteroidetes, and Actinobacteria, which exhibited a higher contribution of homogenizing dispersal assembly and different taxonomy distinct ecological modules when compared with perturbed samples. Specifically, the long-term oil recovery reduced the bacterial taxonomic- and functional-diversity, and increased the community co-occurrence associations in subsurface oil reservoirs. Moreover, distinguished from the perturbed samples, both variation partition analysis and structural equation model revealed that the contents of quartz, NO3- and Cl- significantly structured the α- and ß-diversity in indigenous subsurface bacterial communities. These findings first provide the holistic picture of microbiome in the deep oil reservoirs, which demonstrate the significant impact of human activity on microbiome in deep continental subsurface.

Cloning and physical localization of male-biased repetitive DNA sequences in Spinacia oleracea (Amaranthaceae).

Spinach (Spinacia oleracea Linnaeus, 1753) is an ideal material for studying molecular mechanisms of early-stage sex chromosome evolution in dioecious plants. Degenerate oligonucleotide-primed polymerase chain reaction (DOP-PCR) technique facilitates the retrotransposon-relevant studies by enriching specific repetitive DNA sequences from a micro-dissected single chromosome. We conducted genomic subtractive hybridization to screen sex-biased DNA sequences by using the DOP-PCR amplification products of micro-dissected spinach Y chromosome. The screening yielded 55 male-biased DNA sequences with 30 576 bp in length, of which, 32 DNA sequences (12 049 bp) contained repeat DNA sequences, including LTR/Copia, LTR/Gypsy, simple repeats, and DNA/CMC-EnSpm. Among these repetitive DNA sequences, four DNA sequences that contained a fragment of Ty3-gypsy retrotransposons (SP73, SP75, SP76, and SP77) were selected as fluorescence probes to hybridization on male and female spinach karyotypes. Fluorescence in situ hybridization (FISH) signals of SP73 and SP75 were captured mostly on the centromeres and their surrounding area for each homolog. Hybridization signals primarily appeared near the putative centromeres for each homologous chromosome pair by using SP76 and SP77 probes for FISH, and sporadic signals existed on the long arms. Results can be served as a basis to study the function of repetitive DNA sequences in sex chromosome evolution in spinach.

Genetic and Comparative Genome Analysis of Exiguobacterium aurantiacum SW-20, a Petroleum-Degrading Bacteria with Salt Tolerance and Heavy Metal-Tolerance Isolated from Produced Water of Changqing Oilfield, China.

The genome of Exiguobacterium aurantiacum SW-20 (E. aurantiacum SW-20), a salt-tolerant microorganism with petroleum hydrocarbon-degrading ability isolated from the Changqing Oilfield, was sequenced and analyzed. Genomic data mining even comparative transcriptomics revealed that some genes existed in SW-20 might be related to the salt tolerance. Besides, genes related to petroleum hydrocarbon degradation discovered in genomic clusters were also found in the genome, indicating that these genes have a certain potential in the bioremediation of petroleum pollutants. Multiple natural product biosynthesis gene clusters were detected, which was critical for survival in the extreme conditions. Transcriptomic studies revealed that some genes were significantly up-regulated as salinity increased, implying that these genes might be related to the salt tolerance of SW-20 when living in a high salt environment. In our study, gene clusters including salt tolerance, heavy metal tolerance and alkane degradation were all compared. When the same functional gene clusters from different strains, it was discovered that the gene composition differed. Comparative genomics and in-depth analysis provided insights into the physiological features and adaptation strategies of E. aurantiacum SW-20 in the oilfield environment. Our research increased the understanding of niches adaption of SW-20 at genomic level.