Nitrogen (N) removal from saline wastewater has emerged as a key concern to safeguard environment. High salinity can impede the growth of bacteria responsible for nitrogen removal. The identification of salt-tolerant bacteria capable of nitrogen removal is thus important for wastewater treatment. In this study, a novel strain, Alcaligenes aquatilis DN-1, capable of aerobic-heterotrophic nitrogen removal (AHNR) was isolated from wastewater. The strain DN-1 showed 100 %, 99.97 %, and 85.24 % efficiencies for removing ammonium, nitrite, and nitrate, respectively. Particularly, strain DN-1 exhibited excellent ammonium removal efficiency under 0-6 % salinity. A maximum nitrogen removal rate of 98.92 % was achieved at NaCl concentration of 6 %. Results of transcriptomic analysis indicated that up-regulation of gdhA, gltB and gltD genes was observed, which were involved in the assimilation pathway of ammonium removal. Ammonium removal pathway from hypersaline wastewater by strain DN-1 was accomplished mainly through assimilation. Genes involved in synthesis of ectoine and 5-hydroxyectoine, i.e., ectA, ectB, ectC and ectD, showed significantly high levels of transcriptional expressions, indicating that strain DN-1 balanced osmotic pressure by accumulating ectoine and 5-hydroxyectoine to withstand salinity-induced osmoadaptation. Meanwhile, genes associated with oxidative stress (trxB, trxC, dsbA, dsbB, dsbC and dsbD) were also upregulated to some extent. Genes involved in osmoadaptation and oxidative stress cooperated with ammonium metabolism pathways to counteract salt stress. The study indicated that the isolatedstrain for was highly efficient in eliminating ammonium from wastewater. The findings further offered valuable insights into the adaptation mechanisms of Alcaligenes aquatilis DN-1 in salt wastewater.

In order to improve the digestibility of animal coarse feed, the fermentation conditions of lignin degrading enzyme production by Trametes hirsuta XYG422 were optimized by user of single factor and orthogonal experiments. Scutellaria residue was used as the substrate. The results showed that the optimized medium composition for solid fermentation of Trametes hirsuta XYG422 was as followed: Soluble starch ∶ ammonium sulfate 3∶1, 3 mmol/L Cu2+ and 1.8 mmol/L Mn2+. Under the conditions, manganese peroxidase activity reached 179.37 nmol/(min·g), laccase activity reached 41.68 U/g. The research has certain guiding significance for the production and application of Trametes hirsuta , and also provides novel opportunities to develop livestock feeds with improved fiber digestibility.

Cold stress is one of the major abiotic stresses that limits the growth and development of plants. Improving the cold tolerance of plants is essential to enhance crop productivity in the changing environment. OPEN STOMATA 1 (OST1), also known as sucrose non-fermenting 1 related protein kinases 2.6/2E (SnRK2.6/SnRK2E), has been reported to involved in cold stress response in plants. This interesting protein is confined to expressed in guard cells and vascular system. However, the detailed mechanism of how OST1 regulates cold stress, especially at the metabolomic level is largely unknown. In this study, metabolomic profiling of ost1 mutant and WT Arabidopsis plants under cold stress was investigated. The results showed that ost1-4 mutants displayed cold sensitive phenotypes compared with the WT plant, as evidenced by higher MDA content and electrolyte leakage and lower photosynthetic characteristics. Next, the metabolic changes between ost1-4 and WT plants in response to cold stress was analyzed by using the GC-TOF-MS system. The results showed that numbers of metabolites were identified to be related to OST1 regulated cold stress response. A large portion of the metabolites were carbohydrates and organic acids. The KEGG enrichment analysis revealed that the alanine, aspartate and glutamate metabolism, cyanoamino acid metabolism and citrate cycle (TCA cycle) were presumptive pathways that most related to OST1 regulated cold stress response. Gene expression such as AtGDHs, AtPPC1 and AtAK1 was also in line with the metabolic changes in the presumed pathways. Overall, this study provides fundamental knowledge for understanding the underlying metabolic mechanisms of OST1 mediated cold stress response in plants.

为了获得耐受各种不良环境的多环芳烃(PAHs)降解菌,利用多环芳烃(菲和芘)、重金属(Cu2+、Cr6+)以及氮源缺乏培养基从南阳石油污染土壤中分离筛选一株耐受不良环境的菲芘降解菌,通过形态学特征和分子生物学方法鉴定菌株,并研究菌株对重金属Cr6+和Cu2+、氮源缺乏及酸碱的耐受程度,进一步探究在这些不良环境下菌株对多环芳烃菲和芘的降解效果.结果表明,菌株属于根瘤菌属,命名为F3-1.在液体培养基中,菌株F3-1对重金属Cr6+和Cu2+的耐受质量浓度均为20 mg/L;在氮源缺乏的情况下,菌株能够正常生长;菌株F3-1在pH 5.0和pH 7.4环境下均可以正常生长;菌株F3-1在不良环境下对多环芳烃菲和芘均有很好的降解效果,5 d后在pH 7.4条件下对菲(50 mg/L)的降解率为35.54％,在pH 5.0条件下对芘(50 mg/L)的降解率为53.43％.

This study aimed to investigate the biodegradation of three distinct PAHs: Phenanthrene (Phe), Pyrene (Pyr), and Benzo[a]pyrene (BaP) by using fermentation broth from T. hirsuta culture medium. The results revealed that 2,5-xylidine ameliorates laccase production in T. hirsuta fermentation medium. After 6 days of incubation, T. hirsuta zlh237 fermentation broth (6-day-FFB) showed a higher degradation rate for three PAHs than 11-day fermentation broth (11-day-FFB). Final Phe, Pyr, and BaP degradation rates of 6-day-FFB were 89.35%, 85.92%, and 89.45%, respectively, on the 5th day of incubation. The PAHs biodegradation rate of 6-day-FFB in natural soil samples were lower than in sterilized soil. The Phe, Pyr, and BaP degradation rates of 6-day-FFB were 54.49%, 46.76%, and 51.93% in sterilized soil samples, and 39.37%, 34.00%, 33.99% in natural soil samples, after 15 days incubation, respectively. The high-throughput sequencing analysis revealed that the 6-dayFFB altered the bacterial community structure and enhanced microbial biodiversity of contaminated soil. The PAHs-contaminated soils incubated with 6-day-FFB showed significant increase in well color development than the controls. Principal Component Analysis of Biolog data differentiated the effect of 6-day-FFB and sterilized 6-day-FFB on contaminated soils. It implied that T. hirsuta zlh237 restored the microbiological functioning of the PAHs contaminated soils.

芽孢杆菌(Bacillus)因生长快、表面积大、抗逆性强等优点在重金属污染土壤修复方面表现出了广阔的应用前景.对近年来报道的具有重金属污染土壤修复功能的芽孢杆菌种类进行了总结,梳理了其作用机制,并对其处理重金属污染的分子生物学机理进行了分析归纳,结果显示,已有20种以上芽孢杆菌表现出了重金属污染土壤修复功能,主要修复机制有生物溶解与沉淀、生物吸附与富集以及生物转化作用3种.最后对芽孢杆菌修复重金属污染土壤的前景进行了展望,以期为后续研究提供思路与参考.

为考察磷灰石、石灰和黑麦草对Cd污染土壤的修复效果,通过盆栽试验研究了不同剂量磷灰石(0、6、12、24 g·kg-1风干土,编号为CK、L1、L2、L3)和石灰(1、2、4 g·kg-1风干土,编号为S1、S2、S3)对Cd胁迫下黑麦草生物量、根形态、黑麦草Cd含量、Cd富集量、富集系数、土壤pH、土壤有效态Cd含量等的影响.结果表明,磷灰石、石灰处理(L1,S1除外)显著增加了黑麦草生物量、根长、根表面积、根体积、根尖数、Cd富集量和土壤pH,显著降低了黑麦草Cd含量、Cd富集系数、根平均直径和土壤有效态Cd含量.相关性分析结果表明:除根平均直径为正相关关系外,黑麦草根长、根表面积、根体积、根尖数与土壤有效态Cd含量、黑麦草地上部分及根系Cd含量、Cd富集系数呈显著或极显著负相关关系;除根平均直径为负相关关系外,其他根指标与黑麦草地上部分及根系生物量、Cd富集量呈极显著正相关关系.其中,L3处理黑麦草地上部分及根系生物量达到CK处理(不添加改良剂)的176.0倍和174.4倍;根平均直径相比CK降低了29.4％,根长、根表面积、根体积和根尖数分别为CK处理的20.2、21.0、21.3倍和24.5倍;黑麦草地上部分及根系Cd富集量达到CK处理的89.6倍和100.9倍.研究表明,根形态受土壤有效态Cd含量的影响显著,并可通过影响黑麦草生物量及Cd吸收决定其Cd富集量,施用24 g·kg-1的磷灰石并种植黑麦草能很好地修复Cd污染土壤.

为探究引起河南省汝南县花生白绢病的病原种类及其生物学特性,利用形态学和分子生物学方法对分离自汝南县的花生白绢病原真菌进行鉴定,同时研究了病原菌的生物学特性及室内药剂筛选.结果表明,引起汝南县花生白绢病的病原菌为罗氏阿太菌(Athelia rolfsii),其无性态为齐整小核菌(Sclerotium rolfsii).生物学特性研究表明花生白绢病的病原菌生长的最适温度为30℃,最适pH为6.0.该菌能利用供试的碳源、氮源进行营养生长,但在以葡萄糖、麦芽糖或淀粉为唯一碳源和以尿素作为唯一氮源的培养基上均不能产生菌核.菌核的抑制萌发温度为55℃,时间为10 min.室内抗病药毒力测定结果表明,戊唑醇对罗氏阿太菌的毒力最强,EC50值为0.4629 mg/L.

通过Illumina MiSeq高通量测序技术,对花生根、茎、叶、花不同器官内生细菌16S rRNA的V5～V7可变区进行测序,研究花生内生细菌群落多样性.从花生不同器官内一共获得61396条有效序列和468个OTU(Operational Taxonomic Units).物种分类显示花生内生细菌种类隶属于21个门、43个纲、107个目、177个科和284个属.根部内生细菌优势属为假单胞菌属(Pseudomonas)、慢生根瘤菌属(Bra-dyrhizobium)和魏斯氏菌属(Weissella),相对丰度分别为37.67％、25.13％和7.38％;茎部内生细菌优势属为假单胞菌属(Pseudomonas)和红球菌属(Rhodococcus),相对丰度分别为73.12％和8.88％;叶部内生细菌优势属为假单胞菌属(Pseudomonas)和红球菌属(Rhodococcus),相对丰度分别为78.65％和8.55％;花部内生细菌优势属为假单胞菌属(Pseudomonas),相对丰度为15.15％.PICRUSt功能预测表明,叶部内生细菌中参与调控各种代谢通路的物种丰度最高,茎部和根部次之,花部最低.以上研究结果表明花生内生细菌具有丰富的种群多样性,为今后开发利用花生内生细菌资源奠定了基础.

【目的】利用中国科学院微生物研究所真菌学国家重点实验室分离获得的菌株Trametes hirsuta zlh237,研究生物强化（接种菌株T. hirsuta zlh237发酵液）对污染土壤中3种多环芳烃（PAHs）[Phenanthrene、Pyrene和Benzo[a]pyrene（BaP）]的降解效果,为该菌株在PAHs污染土壤中的应用提供科学依据。【方法】采用高效液相色谱（HPLC）检测7个处理土壤（接种菌株T. hirsuta zlh237发酵液的Phenanthrene、Pyrene和BaP污染土壤分别标记为PheBA、PyrBA和BaPBA,接种灭菌发酵液的污染土壤分别标记为Phe、Pyr和BaP,原始土壤标记为CK）中3种PAHs含量,利用ABTS法检测土壤中漆酶活性,并运用高通量测序技术分析修复后土壤中细菌群落结构的变化。【结果】菌株T. hirsuta zlh237在3种PAHs污染土壤中均能生长,接种菌株发酵液15 d后,3种PAHs均有一定降解,其中BaP降解效果最佳,降解率达33.99%;且菌株T. hirsuta zlh237在3种污染土壤中均能分泌漆酶。高通量测序Alpha多样性指数分析结果表明,污染土壤接种菌株T. hirsuta zlh237发酵液后,Chao1指数和Shannon指数显著增加（P＜0.05）,不同处理土壤样品的Chao1指数和Shannon指数排序均为:PheBA＞PyrBA＞BaPBA＞CK＞Phe＞Pyr＞BaP。Beta多样性的主成分分析（PCA）结果表明,接种菌株T. hirsuta zlh237发酵液能改变污染土壤细菌群落结构组成;在门分类水平上,污染土壤样品中变形菌门（Proteobacteria）为优势门;在属分类水平上,接种菌株T. hirsuta zlh237发酵液的污染土壤样品中鞘氨醇单胞菌属（Sphingomonas）为优势菌属,接种灭菌发酵液的污染土壤Phe和Pyr样品中苯基杆菌属（Phenylobacterium）为优势菌属,而BaP样品中假单胞菌属（Pseudomonas）为优势菌属。【结论】菌株T. hirsuta zlh237发酵液在PAHs污染土壤中能分泌漆酶,对3种PAHs均有一定的降解效果,且能改变污染土壤细菌群落结构组成,在一定程度上对PAHs污染土壤有较好的修复效果。

为了筛选对铅铬污染耐受的小麦品种以及探究其对土壤铅铬积累作用的影响,通过盆栽试验,将混合有菌渣的土壤加入一定量的铅铬溶液,使铅铬在土壤中的质量比分别为1000、300 mg/kg,混匀平衡60 d后,种植郑麦103、温麦19、矮抗58、秋乐168、秋乐2122、豫保1号6个不同品种的小麦.发芽并生长15 d后,对其进行相关指标测定.结果表明,6个试验小麦品种均可以耐受铅铬胁迫.其中,秋乐168最具有生长优势;在对氮、磷、钾的利用上,郑麦103和温麦19对氮、磷有着更多的营养需要,秋乐168和秋乐2122则更偏向于吸收更多的钾;在对土壤中铅铬积累情况上,6个试验小麦品种均可以缓解重金属铅铬的积累.矮抗58可以有效地阻止土壤中铅的持续积累.温麦19对Cr(Ⅵ)的转化相比于其他5个小麦品种具有明显的优势.

通过显色平板初筛与发酵复筛的方法从土壤、果皮样品中分离、筛选高产葡萄糖氧化酶(GOD)的菌株,通过形态观察及分子生物学技术对其进行鉴定,并对其所产葡萄糖氧化酶酶学性质进行初步研究.结果表明,通过初筛得到3株产葡萄糖氧化酶菌株,命名为CY-12、KY-16、PT-22.通过复筛得到1株高产胞外葡萄糖氧化酶的菌株CY-12,GOD活力为194.69 U/mL,并被鉴定为枝孢属(Cladosporium sp.).其所产葡萄糖氧化酶最适反应温度为60℃、最适pH值为6.0,在温度30?80 ℃和pH值4.0?6.0范围内酶稳定性较好,Cu2+对酶活有明显的激活作用;Co2+对酶活有明显的抑制作用.

In order to find a more efficient, economical, and environmentally friendly chemical fertilizer alternative, we have developed a new type of microbial fertilizer. The reported types of functional microorganisms in biofertilizers are mostly single and concentrated in nitrogen-fixing bacteria and phosphate-solubilizing bacteria. Here we evaluate the effect of the compound microbial fertilizer with several kinds of functional bacteria. A field experiment was conducted with five treatments (no-fertilization control, regular fertilization 600 kg ha−1, compound microbial fertilizer 750 kg ha−1, compound microbial fertilizer 900 kg ha−1, compound microbial fertilizer 1050 kg ha−1). The effects of the compound microbial fertilizer on wheat traits, grain yield, soil physical and chemical properties, and microbial community structure were investigated. The results showed that the compound microbial fertilizer as base fertilizer could not only enhance the contents of soil available phosphorus and available potassium but also enhance the grain yield markedly. The compound microbial fertilizer could affect the microbial community, and the change of the microbial community was more correlated with growth period of wheat. The results established that the compound microbial fertilizer which can reduce part of the amount of chemical fertilizer can enhance wheat yield and the recommended dose of the fertilizer is 750 kg ha−1 in the study area.

通过田间试验研究了不同剂量磷灰石(10、20、30、50 g/kg,编号分别为LH1、LH2、LH3和LH4)与黑麦联合作用对Cu污染土壤的修复效果,重点考察了磷灰石对黑麦生物量及Cu吸收、土壤pH及Cu形态转化、土壤酶活性、植物生理指标等的影响.试验结果表明,磷灰石显著提高了土壤pH、黑麦生物量及其Cu吸收量,显著降低了黑麦地上部分及根系Cu含量,其中LH3处理黑麦Cu吸收量最高,达到对照处理的33.38倍;与对照相比,LH1、LH2、LH3和LH4处理土壤可交换态Cu含量显著降低了37.0％、58.9％、89.0％ 和83.3％,碳酸盐结合态Cu含量显著增加了46.6％、63.1％、78.0％ 和93.3％;与对照相比,LH2、LH3和LH4处理显著提高了土壤磷酸酶、过氧化氢酶和脲酶活性,显著提高了黑麦SOD和POD酶活性,显著降低了黑麦MDA含量.综合而言,施用30 g/kg的磷灰石并种植黑麦能够很好地修复Cu污染土壤.

为了提高蜡样芽孢杆菌CP-1菌株对Cr(VI)的还原效果,采用单因素和正交试验,通过摇瓶发酵培养,对影响蜡样芽孢杆菌CP-1菌株还原Cr(VI)的发酵培养基成分和培养条件进行了优化,并研究了最佳发酵条件下的蜡样芽孢杆菌CP-1对Cr(VI)的还原效果.结果表明,蜡样芽孢杆菌CP-1菌株还原Cr(VI)的最佳培养基组成为:1％甘露醇,3％的大豆蛋白胨,0.05％KCl,0.1％CuSO4,在此基础上的最佳培养条件为:pH7.0、6％接种量、45℃培养3 d,在此条件下,Cr(VI)初始浓度为100 mg·L-1时,对Cr(VI)的还原率达99.75％.在Cr(VI)污染的土壤中添加蜡样芽孢杆菌CP-190 d后,土壤中的Cr(VI)含量降低55.15％左右.

为实现玉米秸秆的田间快速分解,采用室内和室外盆栽试验方法对复合菌剂(黑曲霉Aspergillus niger(J4)、枯草芽孢杆菌Bacillus subtilis(A1)和毛栓孔菌Trametes hirsute(XYG422))促玉米秸秆分解效果进行分析,并研究复合菌剂对土壤养分及微生物功能多样性的影响.结果表明,先接种菌株A1和XYG422,间隔2 d后接种菌株J4对玉米秸秆中木质素、纤维素和半纤维素的降解效果优于3种菌株同时接种的处理.玉米秸秆接种复合菌剂40 d时,能显著提高玉米秸秆的降解率(35％)与对照相比提高了13％,但菌剂的不同接种剂量对玉米秸秆的降解差异不明显.施用复合菌剂后,土壤有效磷、速效钾和碱解氮含量增加,且随着培养时间的延长,其有效成分含量呈上升趋势.Biolog结果表明,施用复合菌剂的处理组在20 d和40 d时土壤微生物AWCD及Shannon、Simpson和McIntosh指数与对照(CK20和CK40)相比均有不同程度提高,但菌剂的不同接种剂量之间差异不明显.主成分分析表明,接种复合菌剂后土壤微生物的碳源利用情况有明显差异.对照组CK20和CK40碳源利用种类较少;T1和T2利用碳源较多,种类相似;T3和T4碳源利用种类最多,但利用种类存在一定差异.

In an effort to address public concerns of the long-term stability and ecological risk reduction of Cu and Cd in a farmland located at the Guixi, Jiangxi Province, China, containing approximate to 800mgkg(-1) Cu and 0.8mgkg(-1) Cd soil, were treated in situ by attapulgite, apatite, montmorillonite and lime at the rate: 10, 10, 10 and 4gkg(-1) soil, respectively. Field experiment consisted of 2x3-m plots arranged in a randomised complete block design with each treatment. Soil and plant samples were collected in sixth years post-treatments and analysed for Cu and Cd bioaccessibility, chemical fraction and Cu, Cd concentration in plant tissue. The results indicated that the apatite and lime treatments significantly reduced bioaccessible and exchangeable fractions Cu and Cd in the soil at sixth years post the treatments. Cu and Cd concentration in plant tissue was positively related to the bioaccessibility of Cu and Cd. The treatment used 10g apatite kg(-1) soil appeared to be most effective for overall risk reduction. The Cu and Cd stabilisation and risk reduction by the apatite treatments were accomplished by the induced transformation of labile Cu and Cu species to relatively insoluble forms. This study illustrated that in situ Cu and Cd stabilisation by apatite would be long-term and ecologically safe, which could safeguard human health and ecosystem from Cu and Cd contamination in mining areas.

A pot experiment was set up to test the remediation effects in a Cu contaminated soil by applying of lime(SH1, SH2 and SH3, dosages of 0.1%, 0.2%and 0.4%, respectively)and ryegrass(Secale cereale), according to the determination of growth and Cu accumula-tion of ryegrass, transformation of Cu speciation in soil, and soil microbial community. The results showed that lime significantly increased biomass and Cu accumulation of ryegrass and soil pH, but decreased Cu concentration of aboveground and root of ryegrass. Compared to control, SH1, SH2 and SH3 decreased exchangeable Cu by 58.47%, 87.51% and 74.54%, while increased carbonate bound Cu to 1.36, 1.93 and 1.56 times than control, respectively. The Biolog analysis at 72 h showed that lime had the ability to increase AWCD(average well color development), S(substrate richness), Shannon's, Simpson, and McIntosh diversity index in the descending order of SH2, SH3, SH1 and CK. Lime changed the carbon source utilization patterns of soil microbial communities obviously. SH2 had the highest level of the car-bon source utilization. In conclusion, combining lime of dosage of 0.2%with ryegrass could remediate the Cu contaminated soil.

In order to explore the optimum spore-producing conditions of Bacillus licheniformis DY-1 and Bacillus mucilaginosus XK mixed fermentation,the study was optimized by single factor and orthogonal experiments.Eppendorf 7.5 L fermentor was used to produce spores under the optimum conditions.The results showed that the optimum spore-producing conditions of two Bacillus spp.mixed fermentation were as follows:the seed solution inoculation proportion ofB.mucilaginosus XK 4:1 and B.licheniformis DY-1 (V/V),culture temperature 37 ℃,culture time 60 h and pH 8.0.Under the conditions,the spore count was up to 1.1 × 1011 CFU/ml in Eppendorf 7.5 L fermentor,which was higher than that of shaking flask fermentation (2.0× 1010 CFU/ml).

Trametes hirsuta XYG422 with high laccase activity was selected by liquid fermentation from nine white-rot fungal stocks.Single-factor experiment was designed to optimize the laccase producing ability according to different cultural media and conditions.Then,corn straws were used to assess the degradation by this strain.The optimized nitrogen sources for XYG422 laccase production were corn flour and tartaric acid ammonium.The optimized nutritional ingredients and fermentation conditions were corn flour 40g/L,tartaric acid ammonium 2g/L,incubation temperature of 30℃,culture medium pH value of 8.0,inoculum quantity of five fungal agar plugs (diameter 1cm) and rotary rate of 180r/min.Tween-80 and 2,5-dimethyl aniline at low concentration promoted laccase production.Under the optimized conditions,the laccase activity produced in XYG422 was significantly increased up to 41.6U/mL.Trametes hirsuta XYG422 exhibited the best corn straw biodegradation effect.After 60d inoculation,the lignin degradation rate reached 83.54％,and the cellulose and hemi-cellulose degradation rate was 50.65％ and 19.53％ respectively.