In this paper,a slight halophilic alkaliphile swain,Alkalibacterium sp.F26,which produced high level of intracellular CAT observed in previous research,was selected as a model microbial to explain the responses of this bacterium to oxidative stress.The results indicated that Alkalibacterium sp.F26 had obvious responses to higher concentration (＞1 mmol/L) of H2O2 than that to lower H2O2 (＜1 mmol/L) challenge from the aspects of defensive enzyme synthesis and cofactors level variation.As for catalase production,the activity increased up to 106.54 U/rag protein which was 1.76 fold of the control when cells were challenged by 3 mmol/L H2O2,but its activity only was 1.13 fold when H2P2 was 100 μmol/L.As far as energy state was concerned,ATP production and NAD+ generation were significantly inhibited from 20.55 μmol/L to 17.80 μmol/L and 69.89 μmol/L to 31.77 μmol/L,respectively,leading to the drop of energy charge from 0.77 to 0.68 and the increase of the portion of NADH/NAD+ from 0.08 to 0.41 in the former case.However,these effects were less distinct under lower concentration of H2O2.Except of the condition of 100 μmol/L H2O2,under which the activation of defensive mechanism resulted in an increase of ATE the level of ATP dropped from 22.69 μmol/L of the control to 22.38 μmol/L and 13.70 μmol/L when challenged by 50 μmol/L and 500 μmol/L H2O2.Besides,the concentration of NADH fluctuated and the NAD+ gradually reduced when H2O2 below 1 mmol/L.

Endophytic bacteria reside in most healthy plants;it can not be easily influenced by outer environment.Some endophytic bacteria are beneficial to host plants,such as growth promotion,disease prevention and nitrogen fixation etc.Therefore,endophytic bacteria ale the potential microbial fungicides,it may be widely applied.In this study,endophytic bacteria were isolated from soybcan cultivar Hefeng 25 that was a main soybean cultivar in Heilongjiang province,China.The results indicated that the density of endophytic bacteria varied in different tissues of the plant.It was 3.4×103CFU/g in roots,2.8×103CFU/g in leaves,2.9×102 CFU/g in stems and 1.4×102 CFU/g in seeds.The activity of 121strains against Fusarium oxysporum f.sp.soybean,caused soybean root rot,were assayed.25.6% of them showed antagonistic activity against F. oxysporum f. sp.soybean.One of them,strain TF28 isolated from soybean roots could inhibit the growth of many fungal pathogens.The inhibitory rates against F. oxysporum from different plant species were 80.2%-96.7%.Based on the morphological,physiological and biochemical characteristics as well as the sequence of 16S rRNA,strain TF28 was identified as Bacillus amyloliquefaciens.

Every year, waters on earth receive large quantities of wastewater from industry, agriculture, fish and poultry raising, and municipal sewage treatment plants. Consequently, the aquatic environment on the earth is under a serious challenge from a very large quantity of pollutants such as antibiotics, insecticides, herbicides, hydrocarbons, etc., contained in the domestic wastewater, industrial and agricultural waste water and illegal effluents. In particular, with the development of intensive aquiculture and poultry, the effluent pollution has recently become more and more serious with more attentions. Furthermore more and more chemical pollutants discharged into aquatic environment have been detected with the advancement of analytical techniques. These chemicals can cause toxic effects on water habitats after discharged into aquatic environment. However, microorganisms have many key functions in pollution control. In this review, applications of microorganism in the degradation of chemicals in aquatic environments are reviewed. It was concluded that most applications of microorganisms degrading chemicals focused on aquaculture waters, whereas other aquatic systems (such as river, lake, sea, coastal waters) have been scarcely studied.

Strain NCIMB 10467, a lignin degrader, was reclassified as genus Burkholderia according to its 16S rDNA sequence. It seems that the metabolism of protocatechuate by this strain is diverse under the induction of various substrates. A 9505-bp DNA fragment extending from α conserved region of the gene, which encodes β subunit of orthocleavage protocatechuate 3, 4-dioxygenase(P34D; EC 1.13.11.3),was obtained by genome walking. Sequence analysis revealed two deduced open reading frames, pcaG and pcaH, encoding the α and β subunits of P34D respectively in this fragment. The P34D activity could be detected when pcaGH were expressed in E. Coli and the disruption of pcaH in strain NCIMB 10467 has lead to loss of its ability to catabolize protocatechuate. It was proved that the cloned pcaGH were encoding a functional protocatechuate 3, 4-dioxygenase which was necessary for the protocatechuate metabolism in this strain.

A 460 bp internal fragment of the AcrA gene from Vibrio alginolyticus strain HY9901 was amplified by PCR with designed primers and the unknown flanking sequence of 5 '- and 3 '- ends of the AcrA gene was finally characterized by inverse PCR and nested PCR. Sequence analysis showed the AcrA gene contained 1101 bp ORF encoding 366 amino acids and the deduced amino acid sequence of the precursor from Vibrio alginolyticus strain HY9901 showed significant homology with the putative protein of other Vibrio species. The AcrA shows 76%, 73%, 71% and 70% homology with V.vulnificus strain YJ016, V. parahaemolyticus strain RIMD 2210633, V. splendidus strain 12B01 and V. cholerae O1 biovar eltor str. N16961 respectively.

A strain,WJ-100, with high flocculating activity was screened from activated sludge.Its optimum pH was 6.5 and optimum temperature was 25℃～40℃.Its shaking speed was in the range of 80～240 r/min. Na~ + ,K~ + ,Ca~ 2 + and Fe~ 3+ could accelerate flocculation .Ca~ 2+ did the most obviously.WJ-100 can use various saccharides as good sources of carbon,the flocculating rate reached 99.2%,99.8%,even 100%.The strain could flocculate very well when pH of Kaolin clay suspension was 2.0～10.0.WJ-100 had high flocculation efficiency in the conditions of relatively large pH value, temperature, sources of carbon, shaking speed, mixing speed etc.and showed fine resaerch and application importance.

On recently years,the tuberculosis shows the characteristic of higher incidence、 infection、drug-resistance、and Morbidity。However,the emphasis and difficult is preventing and controling of multidrug resistant tuberculosis.Its nosocomial and societal causes of occuring and prevailing were analyzed and control measures from seven facets were expounded in this article.Those include prevention knowledge widely,strengthen management and supervision of floating population,improve ability of diagnosis and therepy,develop combinasion treatment of traditional chinese medicine and western medicine and other assistant treatment, prevent community and nosocomial infection,perfect the drug-resistant surveillance system,carry out the study of new drug 、measure and treatment to anti-tuberculosis actively.

Raising earthworms in boxes with excess sludge is conducted.It is concluded that excess sludge is eatable to earthworms ,and feeding condition is≤30cm filling thickness with fresh excess sludge each time,≤20cm up-filling thickness with rotten-lumpy excess sludge each time.

Dissimilatory Fe(Ⅲ)reduction is the important process in Biogeochemical cycle.This paper gives a systematic introduction to the types of dissimilatory Fe(Ⅲ)reduction,mechanism of insoluble Fe(Ⅲ)oxidizes reduction and the advances of molecular biology in- volved in Fe(Ⅲ)reduction.The status of the applications of dissimilatory Fe(Ⅲ)reduction in environmental contaminant treatment were also discussed.

Bacterial disease is still the important disease hazardous to health of human being and animals.The bacterial mutation technique is an important bacterial research technique,including traditional physical and chemical and biological method,and modern genetic mutation technique.The bacterial genetic mutation technique is one of the research focus in bacteriology nowadays,the mutation strategy varies with different kinds of genetic:mutation technique.The development and application of bacterial mutation technique offers new tools for research on new bacterial vaccine,bacterial genetic function and genetic therapy etc.