Two heat shock cognate 70 genes involved in spermatogenesis regulate the male fertility of Zeugodacus cucurbitae, as potential targets for pest control.

The melon fly Zeugodacus cucurbitae Coquillett (Diptera: Tephritidae) is an agricultural quarantine pest threatening fruit and vegetable production. Heat shock cognate 70 (Hsc70), which is a homolog of the heat shock protein 70 (Hsp70), was first discovered in mice testes and plays an important role in spermatogenesis. In this study, we identified and cloned five Hsc70 genes from melon fly, namely ZcHsc70_1/2/3/4/5. Phylogenetic analysis showed that these proteins are closely related to Hsc70s from other Diptera insects. Spatiotemporal expression analysis showed that ZcHsc70_1 and ZcHsc70_2 are highly expressed in Z. cucurbitae testes. Fluorescence in situ hybridization further demonstrated that ZcHsc70_1 and ZcHsc70_2 are expressed in the transformation and maturation regions of testes, respectively. Moreover, RNA interference-based suppression of ZcHsc70_1 or ZcHsc70_2 resulted in a significant decrease of 74.61% and 63.28% in egg hatchability, respectively. Suppression of ZcHsc70_1 expression delayed the transformation of sperm cells to mature sperms. Meanwhile, suppression of ZcHsc70_2 expression decreased both sperm cells and mature sperms by inhibiting the meiosis of spermatocytes. Our findings show that ZcHsc70_1/2 regulates spermatogenesis and further affects the male fertility in the melon fly, showing potential as targets for pest control in sterile insect technique by genetic manipulation of males.

Vesicoprostatic muscle reconstruction: a step further for immediate and early urinary continence.

OBJECTIVES: The vesicoprostatic muscle (VPM) is a longitudinal smooth muscle that originates from the trigone of the bladder or the opening of the ureter and is involved in urination as part of the detrusor apron. We explored the effect of VPM reconstruction on immediate and early recovery of urinary continence in patients undergoing robot-assisted laparoscopic radical prostatectomy (RALP). PATIENTS AND METHODS: A total of 523 patients with localized prostate cancer were enrolled from June 2018 to June 2020. All patients were diagnosed in our department based on magnetic resonance imaging and pathological findings on prostate biopsy. After 1:1 propensity score matching, 105 patient pairs were matched. The study was approved by our institutional review board and all surgeries were performed by three experienced high-volume surgeons. Demographic data, total operation time, pathological outcomes, the urinary continence rates of the two groups at different times after RALP, and factors influencing postoperative urinary continence after RALP were recorded. Student's t test was used to compare continuous variables and the Pearson χ2 test to compare categorical variables. Logistic regression analysis was used to identify factors affecting immediate and early postoperative urinary control. RESULTS: VPM reconstruction promoted immediate and early recovery of urinary continence (immediate continence, 66.67 vs. 40.00%, P = 0.000; 3-month continence, 80.95 vs. 64.76%, P = 0.008). CONCLUSIONS: VPM reconstruction improved immediate and early urinary continence in patients who underwent RALP.

Posttraumatic checkrein deformity following isolated Lauge-Hansen pronation external rotation stage IV malleolar fracture-a case report and literature review.

The checkrein deformity is characterized by flexion contracture of the interphalangeal joint and extension contracture of the metatarsophalangeal joint. It is a rare condition occurring after lower extremity trauma, especially a malleolar fracture. Little is known about the possible cause and therapeutic strategy. This unique case presents a 20-year-old male patient with a diagnosis of the checkrein deformity secondary to open reduction and internal fixation of a Lauge-Hansen pronation external rotation stage IV malleolar fracture. After performing a detailed physical examination, radiographic evaluation, and ultrasonography, open exploration was performed to remove the hardware and correct the deformity with sole tenolysis of the flexor hallucis longus (FHL). In the 4-month follow-up, no recurrence of the checkrein deformity was observed. This deformity was caused by FHL adhesion. Interosseous membrane injury and fibular fracture together with local hematomas increases the risk of FHL adhesion. Open exploration and tenolysis of the FHL are feasible options to correct the checkrein deformity.

Perioperative Protocol of Ankle Fracture and Distal Radius Fracture Based on Enhanced Recovery after Surgery Program: A Multicenter Prospective Clinical Controlled study.

Background: The enhanced recovery after surgery (ERAS) program is aimed to shorten patients' recovery process and improve clinical outcomes. This study aimed to compare the outcomes between the ERAS program and the traditional pathway among patients with ankle fracture and distal radius fracture. Methods: This is a multicenter prospective clinical controlled study consisting of 323 consecutive adults with ankle fracture from 12 centers and 323 consecutive adults with distal radial fracture from 13 centers scheduled for open reduction and internal fixation between January 2017 and December 2018. According to the perioperative protocol, patients were divided into two groups: the ERAS group and the traditional group. The primary outcome was the patients' satisfaction of the whole treatment on discharge and at 6 months postoperatively. The secondary outcomes include delapsed time between admission and surgery, length of hospital stay, postoperative complications, functional score, and the MOS item short form health survey-36. Results: Data describing 772 patients with ankle fracture and 658 patients with distal radius fracture were collected, of which 323 patients with ankle fracture and 323 patients with distal radial fracture were included for analysis. The patients in the ERAS group showed higher satisfaction levels on discharge and at 6 months postoperatively than in the traditional group (P < 0.001). In the subgroup analysis, patients with distal radial fracture in the ERAS group were more satisfied with the treatment (P=0.001). Furthermore, patients with ankle fracture had less time in bed (P < 0.001) and shorter hospital stay (P < 0.001) and patients with distal radial fracture received surgery quickly after being admitted into the ward in the ERAS group than in the traditional group (P=0.001). Conclusions: Perioperative protocol based on the ERAS program was associated with high satisfaction levels, less time in bed, and short hospital stay without increased complication rate and decreased functional outcomes.

Mixed Reality: A Step Further for Planning Complex Renal Tumors (RENAL Nephrometry Score of 7 or Higher).

Objectives: Mixed reality (MR) technology has emerged in recent years and allows three-dimensional visualization, multiangle observation, remote vision, and virtual-real interaction. This study aims to explore the influence of MR technology on the outcomes and strategy planning of robotic surgery for complex renal tumors. Patients and Methods: A total of 92 patients with complex renal tumors were enrolled in this study from June 2018 to June 2020. All patients were found to have tumors by magnetic resonance imaging (MRI) in our department. This trial follows CONSORT guidelines and adopts a single-blind parallel design and randomizes patients with a random number table. The study was approved by the institutional review board, and written informed consent was obtained from each participant. All surgeries were performed by three experienced and high-volume surgeons. The demographic indicators, intraoperative and postoperative complications, renal function outcomes, pathological results, and surgical strategies were recorded. Student's t-test and Wilcoxon rank-sum test were used to compare continuous variables, and Pearson's chi-squared and Fisher's exact tests were used to compare categorical variables. Results: Warm ischemia time (WIT) mainly comprises tumor resection time and reconstruction time, and the reconstruction time accounts for a larger proportion. For urologists treating complex renal tumors, MR technology can help them reduce the warm ischemia time (21.3 ± 4.0 vs 23.6 ± 5.9 minutes, p = 0.031), reconstruction time (15.4 ± 3.8 vs 17.2 ± 4.2 minutes, p = 0.034), estimated blood loss (p = 0.044), operation time (125.7 ± 26.3 vs 144.6 ± 27.9 minutes, p = 0.001), and intraoperative complications (p = 0.030). Conclusions: MR-assisted surgery can reduce the incidence of intraoperative complications and improve perioperative outcomes, and MR may be a good preoperative tool for planning complex renal tumor surgery.

Step-by-step and orderly lowering of the height of inferior vena cava tumor thrombus is the key to robot-assisted thrombectomy for Mayo III/IV tumor thrombus.

BACKGROUND: The surgical management of Mayo III/IV tumor thrombi is difficult and risky, and robotic surgery is even more difficult. The purpose of this study was to introduce the step-by-step and orderly lowering of the height of inferior vena cava tumor thrombus, which was the core technique of robot operation for Mayo III/IV tumor thrombus. METHOD: A total of 18 patients were included in this study. The average tumor thrombus height was 2.4 cm above the level of the second porta hepatis (SPH), and 9 patients were prepared for cardiopulmonary bypass (CPB) before surgery. During the operation, the height of the tumor thrombus was lowered orderly for 2-3 times, and the blood flow blocking method was changed sequentially. The CPB was required when tumor thrombus in the atrium; After the height of the thrombus was lowered to the atrium entrance, CPB was stopped and the blood flow was blocked in the upper- and retro-hepatic inferior vena cava (IVC); After the tumor thrombus continued to descend to the lower part of the SPH, liver blood flow could be restored, and then, the blood flow was simply blocked in the retro-hepatic IVC to complete the removal of the thrombus and the repair or resection of the IVC. Finally, the diseased kidney and renal vein were removed. RESULTS: All operations were successfully completed, and 2 cases were transferred to laparotomy. Seven cases received CPB, while the other 11 did not. 15 patients underwent two times of the lowering of the tumor thrombus, 2 patients underwent one time and 1 patient underwent three times. The mean liver/IVC dissociation and vascular suspension time was 22.0 min. All patients had less than Clavien-Dindo grade III complications, no serious complications occurred during operation, and no patient died within 90 days. CONCLUSIONS: The step-by-step and orderly decline of tumor thrombus height is the key to the success of robot Mayo III / IV tumor thrombus surgery. This method can shorten FPH and CPB time and improve the success rate of surgery.

[PI-RADS score of prostate multi-parametric magnetic resonance imaging predicts pathological features of prostate cancer: An imaging to whole-mount pathology matching study].

OBJECTIVE: To explore the value of the prostate imaging reporting and data system (PI-RADS) score of prostate multi-parametric magnetic resonance imaging (mpMRI) in predicting the pathological features of PCa based on matching images and whole-mount pathology images. METHODS: This retrospective study included 318 cases of PCa treated by radical prostatectomy in our hospital from August 2016 to December 2018, with preoperative mpMRI images and complete whole-mount pathological sections. We obtained PI-RADS scores on the mpMRI lesions corresponding to the cancer lesions, evaluated the Gleason scores, pT stages, pN stages and cribriform structure, and compared them between different groups using Chi-square test or Fisher's exact test. We evaluated the efficiency of the PI-RADS score in distinguishing different pathological features by ROC curve analysis, and obtained the corresponding area under the curve (AUC) and 95% confidence interval (CI). RESULTS: The 318 patients averaged 69 years of age, with a median preoperative PSA level of 11.0 µg/L and a median tumor diameter of 1.8 cm. The PI-RADS score was significantly correlated with the Gleason score, pT stage, pN stage and cribriform structure (all P < 0.01), with AUCs of 0.773 (95% CI: 0.704－0.843) for distinguishing Gleason scores (3+3 vs >3+3), 0.748 (95% CI: 0.694－0.803) for distinguishing pT stages (T2 vs >T2), 0.700 (95% CI: 0.598－0.802) for distinguishing pN stages (N0 vs N1), and 0.831 (95% CI: 0.786－0.876) for distinguishing the cribriform structure (negative vs positive). CONCLUSION: The preoperative PI-RADS score of mpMRI in PCa patients is significantly correlated with postoperative pathological features, and therefore can be used for risk stratification of the malignancy.

Candidatus Kaistella beijingensis sp. nov., Isolated from a Municipal Wastewater Treatment Plant, Is Involved in Sludge Foaming.

Biological foaming (or biofoaming) is a frequently occurring problem in wastewater treatment plants (WWTPs) and is attributed to the overwhelming growth of filamentous bulking and foaming bacteria (BFB). Biological foaming has been intensively investigated, with BFB like Microthrix and Skermania having been identified from WWTPs and implicated in foaming. Nevertheless, studies are still needed to improve our understanding of the microbial diversity of WWTP biofoams and how microbial activities contribute to foaming. In this study, sludge foaming at the Qinghe WWTP of China was monitored, and sludge foams were investigated using culture-dependent and culture-independent microbiological methods. The foam microbiomes exhibited high abundances of Skermania, Mycobacterium, Flavobacteriales, and Kaistella. A previously unknown bacterium, Candidatus Kaistella beijingensis, was cultivated from foams, its genome was sequenced, and it was phenotypically characterized. Ca. K. beijingensis exhibits hydrophobic cell surfaces, produces extracellular polymeric substances (EPS), and metabolizes lipids. Ca. K. beijingensis abundances were proportional to EPS levels in foams. Several proteins encoded by the Ca. K. beijingensis genome were identified from EPS that was extracted from sludge foams. Ca. K. beijingensis populations accounted for 4 to 6% of the total bacterial populations in sludge foam samples within the Qinghe WWTP, although their abundances were higher in spring than in other seasons. Cooccurrence analysis indicated that Ca. K. beijingensis was not a core node among the WWTP community network, but its abundances were negatively correlated with those of the well-studied BFB Skermania piniformis among cross-season Qinghe WWTP communities. IMPORTANCE Biological foaming, also known as scumming, is a sludge separation problem that has become the subject of major concern for long-term stable activated sludge operation in decades. Biological foaming was considered induced by foaming bacteria. However, the occurrence and deterioration of foaming in many WWTPs are still not completely understood. Cultivation and characterization of the enriched bacteria in foaming are critical to understand their genetic, physiological, phylogenetic, and ecological traits, as well as to improve the understanding of their relationships with foaming and performance of WWTPs.

Responses of soil microbiome to steel corrosion.

The process of microbiologically influenced corrosion (MIC) in soils has received widespread attention. Herein, long-term outdoor soil burial experiments were conducted to elucidate the community composition and functional interaction of soil microorganisms associated with metal corrosion. The results indicated that iron-oxidizing (e.g., Gallionella), nitrifying (e.g., Nitrospira), and denitrifying (e.g., Hydrogenophaga) microorganisms were significantly enriched in response to metal corrosion and were positively correlated with the metal mass loss. Corrosion process may promote the preferential growth of the abundant microbes. The functional annotation revealed that the metabolic processes of nitrogen cycling and electron transfer pathways were strengthened, and also that the corrosion of metals in soil was closely associated with the biogeochemical cycling of iron and nitrogen elements and extracellular electron transfer. Niche disturbance of microbial communities induced by the buried metals facilitated the synergetic effect of the major MIC participants. The co-occurrence network analysis suggested possible niche correlations among corrosion related bioindicators.

Bacteria and Metabolic Potential in Karst Caves Revealed by Intensive Bacterial Cultivation and Genome Assembly.

Karst caves are widely distributed subsurface systems, and the microbiomes therein are proposed to be the driving force for cave evolution and biogeochemical cycling. In past years, culture-independent studies on the microbiomes of cave systems have been conducted, yet intensive microbial cultivation is still needed to validate the sequence-derived hypothesis and to disclose the microbial functions in cave ecosystems. In this study, the microbiomes of two karst caves in Guizhou Province in southwest China were examined. A total of 3,562 bacterial strains were cultivated from rock, water, and sediment samples, and 329 species (including 14 newly described species) of 102 genera were found. We created a cave bacterial genome collection of 218 bacterial genomes from a karst cave microbiome through the extraction of 204 database-derived genomes and de novo sequencing of 14 new bacterial genomes. The cultivated genome collection obtained in this study and the metagenome data from previous studies were used to investigate the bacterial metabolism and potential involvement in the carbon, nitrogen, and sulfur biogeochemical cycles in the cave ecosystem. New N2-fixing Azospirillum and alkane-oxidizing Oleomonas species were documented in the karst cave microbiome. Two pcaIJ clusters of the ß-ketoadipate pathway that were abundant in both the cultivated microbiomes and the metagenomic data were identified, and their representatives from the cultivated bacterial genomes were functionally demonstrated. This large-scale cultivation of a cave microbiome represents the most intensive collection of cave bacterial resources to date and provides valuable information and diverse microbial resources for future cave biogeochemical research.IMPORTANCE Karst caves are oligotrophic environments that are dark and humid and have a relatively stable annual temperature. The diversity of bacteria and their metabolisms are crucial for understanding the biogeochemical cycling in cave ecosystems. We integrated large-scale bacterial cultivation with metagenomic data mining to explore the compositions and metabolisms of the microbiomes in two karst cave systems. Our results reveal the presence of a highly diversified cave bacterial community, and 14 new bacterial species were described and their genomes sequenced. In this study, we obtained the most intensive collection of cultivated microbial resources from karst caves to date and predicted the various important routes for the biogeochemical cycling of elements in cave ecosystems.

Pheochromocytoma with delayed tumor thrombus detection in renal vein: A case report.

BACKGROUND: Pheochromocytomas with inferior vena cava (IVC) or renal vein tumor thrombus are rare. Surgical management is the first choice. CASE SUMMARY: We presented a 42-year-old man with adrenal pheochromocytoma and delayed tumor thrombus detection in the renal vein at the entrance of the IVC three months after adrenalectomy. We performed laparoscopic adrenalectomy during the first surgery and robot-assisted laparoscopic nephrectomy and resection of tumor thrombus during the second surgery. CONCLUSION: We report the surgical management of a patient with adrenal pheochromocytoma with tumor thrombus at the entrance of the IVC. Robot-assisted laparoscopic surgery is safe and efficient.

Early High Cerebrospinal Fluid Glutamate: A Potential Predictor for Delayed Cerebral Ischemia after Aneurysmal Subarachnoid Hemorrhage.

Delayed cerebral ischemia (DCI) is an important complication after aneurysmal subarachnoid hemorrhage (aSAH). Early identification of cerebrospinal fluid (CSF) markers is helpful for warning of impending DCI. This study assessed whether early high CSF glutamate levels can be observed in aSAH patients who later developed DCI. In this prospective clinical study, patients with normal pressure hydrocephalus or aSAH were enrolled. We found that the early CSF levels of glutamate were significantly elevated in aSAH patients compared to patients with normal pressure hydrocephalus. There was a significant difference in early CSF levels of glutamate between aSAH patients without DCI and with DCI. The early CSF levels of glutamate are significantly related to the Hunt and Hess grade, the World Federation of Neurological Surgeons (WFNS) grade, and the modified Fisher score on admission and occurrence of DCI in aSAH patients. Preliminary evidence of this study suggests that early high CSF glutamate levels are correlated with DCI in aSAH patients.

Efficacy of cattle encephalon glycoside and ignotin in patients with acute cerebral infarction: a randomized, double-blind, parallel-group, placebo-controlled study.

Cattle encephalon glycoside and ignotin (CEGI) injection is a compound preparation formed by a combination of muscle extract from healthy rabbits and brain gangliosides from cattle, and it is generally used as a neuroprotectant in the treatment of central and peripheral nerve injuries. However, there is still a need for high-level clinical evidence from large samples to support the use of CEGI. We therefore carried out a prospective, multicenter, randomized, double-blind, parallel-group, placebo-controlled study in which we recruited 319 patients with acute cerebral infarction from 16 centers in China from October 2013 to May 2016. The patients were randomized at a 3:1 ratio into CEGI (n = 239; 155 male, 84 female; 61.2 ± 9.2 years old) and placebo (n = 80; 46 male, 34 female; 63.2 ± 8.28 years old) groups. All patients were given standard care once daily for 14 days, including a 200 mg aspirin enteric-coated tablet and 20 mg atorvastatin calcium, both taken orally, and intravenous infusion of 250-500 mL 0.9% sodium chloride containing 40 mg sodium tanshinone IIA sulfonate. Based on conventional treatment, patients in the CEGI and placebo groups were given 12 mL CEGI or 12 mL sterile water, respectively, in an intravenous drip of 250 mL 0.9% sodium chloride (2 mL/min) once daily for 14 days. According to baseline National Institutes of Health Stroke Scale scores, patients in the two groups were divided into mild and moderate subgroups. Based on the modified Rankin Scale results, the rate of patients with good outcomes in the CEGI group was higher than that in the placebo group, and the rate of disability in the CEGI group was lower than that in the placebo group on day 90 after treatment. In the CEGI group, neurological deficits were decreased on days 14 and 90 after treatment, as measured by the National Institutes of Health Stroke Scale and the Barthel Index. Subgroup analysis revealed that CEGI led to more significant improvements in moderate stroke patients. No drug-related adverse events occurred in the CEGI or placebo groups. In conclusion, CEGI may be a safe and effective treatment for acute cerebral infarction patients, especially for moderate stroke patients. This study was approved by the Ethical Committee of Peking University Third Hospital, China (approval No. 2013-068-2) on May 20, 2013, and registered in the Chinese Clinical Trial Registry (registration No. ChiCTR1800017937).

Casimicrobium huifangae gen. nov., sp. nov., a Ubiquitous "Most-Wanted" Core Bacterial Taxon from Municipal Wastewater Treatment Plants.

Microorganisms in wastewater treatment plants (WWTPs) play a key role in the removal of pollutants from municipal and industrial wastewaters. A recent study estimated that activated sludge from global municipal WWTPs harbors 1 × 109 to 2 × 109 microbial species, the majority of which have not yet been cultivated, and 28 core taxa were identified as "most-wanted" ones (L. Wu, D. Ning, B. Zhang, Y. Li, et al., Nat Microbiol 4:1183-1195, 2019, https://doi.org/10.1038/s41564-019-0426-5). Cultivation and characterization of the "most-wanted" core bacteria are critical to understand their genetic, physiological, phylogenetic, and ecological traits, as well as to improve the performance of WWTPs. In this study, we isolated a bacterial strain, designated SJ-1, that represents a novel cluster within Betaproteobacteria and corresponds to OTU_16 within the 28 core taxa in the "most-wanted" list. Strain SJ-1 was identified and nominated as Casimicrobium huifangae gen. nov., sp. nov., of a novel family, Casimicrobiaceae. C. huifangae is ubiquitously distributed and is metabolically versatile. In addition to mineralizing various carbon sources (including carbohydrates, aromatic compounds, and short-chain fatty acids), C. huifangae is capable of nitrate reduction and phosphorus accumulation. The population of C. huifangae accounted for more than 1% of the bacterial population of the activated sludge microbiome from the Qinghe WWTP, which showed seasonal dynamic changes. Cooccurrence analysis suggested that C. huifangae was an important module hub in the bacterial network of Qinghe WWTP.IMPORTANCE The activated sludge process is the most widely applied biotechnology and is one of the best ecosystems to address microbial ecological principles. Yet, the cultivation of core bacteria and the exploration of their physiology and ecology are limited. In this study, the core and novel bacterial taxon C. huifangae was cultivated and characterized. This study revealed that C. huifangae functioned as an important module hub in the activated sludge microbiome, and it potentially plays an important role in municipal wastewater treatment plants.

Contrast-enhanced ultrasound in detecting wall invasion and differentiating bland from tumor thrombus during robot-assisted inferior vena cava thrombectomy for renal cell carcinoma.

BACKGROUND: Vena cava thrombus is one of the main clinical manifestations of locally aggressive renal cell carcinoma (RCC). Inferior vena cava (IVC) wall invasion and presence of bland thrombus could affect the surgical outcome. This study aims to assess the value of contrast-enhanced ultrasound (CEUS) in detecting wall invasion and differentiating bland thrombus from tumor thrombus during robot-assisted IVC thrombectomy for RCC. METHODS: The intraoperative CEUS findings of 60 patients with RCC accompanied by IVC tumor thrombus were retrospectively analyzed. The CEUS features were compared with the intra- and post-operative pathological findings. CEUS in patients with wall invasion showed that the tumor thrombus was enhanced synchronously with the IVC wall, and the continuity of the IVC wall was lost. In contrast, in patients without wall invasion, CEUS showed that the contrast agent could pass between the tumor thrombus and the IVC wall, and the continuity of IVC wall was good. Typically, contrast-enhanced perfusion was seen in tumor thrombus but not in bland thrombus. The sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of CEUS were statistically analyzed. RESULTS: The sensitivity, specificity, accuracy, positive predictive value, and negative predictive value of the typical enhancement mode of CEUS were 93.1, 93.5, 93.3, 93.1, and 93.5% in identifying wall invasion and 100, 96, 96.7, 83.3, and 100% in differentiating bland thrombus from tumor thrombus, respectively. There were excellent inter-observer agreements for identifying IVC wall invasion and differentiating bland thrombus from tumor thrombus with kappa coefficients of 0.90 and 0.97. CONCLUSIONS: The present study indicates that intraoperative CEUS plays an important role in robot-assisted IVC thrombectomy for RCC. It can detect wall invasion and differentiate bland thrombus from tumor thrombus, thus offering real-time information to the operator during surgery.

A water-soluble dual-site fluorescent probe for the rapid detection of cysteine with high sensitivity and specificity.

A water-soluble turn-on fluorescent probe has been rationally designed and synthesized to distinguish Cys from Hcy and GSH in less than five seconds. It has high sensitivity and strong anti-interference ability to other amino acids and ions. Its ultra-rapid detection of Cys in aqueous systems could be attributed to dual response sites imparted by the probe.

Diversity, Distribution and Co-occurrence Patterns of Bacterial Communities in a Karst Cave System.

Caves are typified by their permanent darkness and a shortage of nutrients. Consequently, bacteria play an important role in sustaining such subsurface ecosystems by dominating primary production and fueling biogeochemical cycles. China has one of the world's largest areas of karst topography in the Yunnan-Guizhou Plateau, yet the bacteriomes in these karst caves remain unexplored. In this study, bacteriomes of eight karst caves in southwest China were examined, and co-occurrence networks of cave bacterial communities were constructed. Results revealed abundant and diversified bacterial communities in karst caves, with Proteobacteria, Actinobacteria, and Firmicutes being the most abundant phyla. Statistical analysis revealed no significant difference in bacteriomes among the eight caves. However, a PCoA plot did show that the bacterial communities of 128 cave samples clustered into groups corresponding to sampling types (air, water, rock, and sediment). These results suggest that the distribution of bacterial communities is driven more by sample types than the separate caves from which samples were collected. Further community-level composition analysis indicated that Proteobacteria were most dominant in water and air samples, while Actinobacteria dominated the sediment and rock samples. Co-occurrence analysis revealed highly modularized assembly patterns of the cave bacterial community, with Nitrosococcaceae wb1-P19, an uncultured group in Rokubacteriales, and an uncultured group in Gaiellales, being the top-three keystone members. These results not only expand our understanding of cave bacteriomes but also inspires functional exploration of bacterial strains in karst caves.

Acidibrevibacterium fodinaquatile gen. nov., sp. nov., isolated from acidic mine drainage.

A heterotrophic and acidophilic bacterial strain, G45-3T, was isolated from acidic mine drainage sampled in Fujian Province, PR China. Cells of strain G45-3T were Gram-stain-negative, non-spore-forming, non-motile and rod-shaped. Catalase and oxidase activities were positive. Strain G45-3T grew aerobically at 20-45 °C (optimum, 37 °C) and at pH 2.5-5.0 (optimum, pH 4.0). Photosynthetic pigments were not produced. Analysis of 16S rRNA gene sequences showed that strain G45-3T was phylogenetically related to different members of the family Acetobacteraceae, and the sequence identities to Acidisphaera rubrifaciens JCM 10600T, Rhodovastum atsumiense G2-11T and Rhodopila globiformis ATCC 35887T were 95.9 , 95.3 and 95.3 %, respectively. Strain G45-3T contained ubiquinone-10 as its respiratory quinone. The major polar lipids were determined to be diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, phosphatidylcholine, an unidentified aminophospholipid and an unidentified aminolipid. The predominant fatty acids were cyclo-C19 : 0ω8c, C18 : 1ω7c, C16 : 0 and C18 : 0. The genome of G45-3T consists of one chromosome (3 907 406 bp) and three plasmids (68 344, 45 771 and 16 090 bp), with an average G+C content of 65.9 mol%. Based on the results of phenotypic and genomic analyses, it is concluded that strain G45-3T represents a novel species of a new genus, for which the name Acidibrevibacterium fodinaquatile gen. nov., sp. nov. is proposed. A. fodinaquatile is nominated as type species and its type strain is G45-3T (=CGMCC 1.16069T=KCTC 62275T).

Vallitalea okinawensis sp. nov., isolated from Okinawa Trough sediment and emended description of the genus Vallitalea.

A polyphasic study was conducted to characterize an obligately anaerobic bacterial strain, S15T, that was isolated from Okinawa Trough sediment. Strain S15T was Gram-stain-negative, non-motile and rod-shaped. Spores were not observed. Strain S15T grew anaerobically at 20-35 °C (optimum at 25-30 °C) and at pH range of 6.0-8.5 (optimum at 7.5). Analysis of 16S rRNA gene sequences showed that strain S15T was phylogenetically related to Vallitalea guaymasensis Ra1766G1T (94.0 %) and Vallitalea pronyensis FatNI3T (93.1 %). The major polar lipids were diphosphatidylglycerol, phosphatidylglycerol and glycolipids. The predominant fatty acids of strain S15T were iso-C15 : 0, anteiso-C15 : 0, iso-C16 : 0 and C16 : 0. The draft genome was 5.86 Mb with a DNA G+C content of 33.9 mol%. A total of 5285 genes were predicted and, of those, 4669 genes were annotated. The genome data supported the result that strain S15T assimilated various carbon sources. On the basis of unique phenotypic, chemotaxonomic and phylogenetic comparisons, strain S15T is proposed to represent a novel species within the genus Vallitalea, and the name Vallitaleaokinawensis sp. nov. is proposed. The type strain is S15T=CGMCC 1.5231T=KCTC 15675T.