Carbohydrate Fermentation Patterns of Neisseria meningitidis Determined by a Microtiter Method

A carbohydrate fermentation technique has been developed and compared to the standard fermentation test with cystine-Trypticase-semisolid agar for the identification of Neisseria meningitidis. This new method utilizes Mueller-Hinton broth as a basal substrate and is performed with microtiter methods. By using Mueller-Hinton broth with and without the addition of antibiotics, the method can be adjusted to test the fermentation patterns of all of the Neisseria including N. gonorrhoeae.     

休眠期间油桃花芽碳水化合物代谢及其相关基因的表达变化

以十年生大田和三年生盆栽‘曙光’油桃花芽为材料,分别测定了其休眠期碳水化合物含量、糖代谢相关基因的季节性表达及低温处理下相关基因的表达变化,旨在探讨碳水化合物及低温与休眠的关系。结果表明：休眠期间可溶性糖（主要是蔗糖）含量逐渐增加,淀粉含量则呈相反趋势。糖代谢相关基因表达明显不同：腺苷二磷酸葡萄糖焦磷酸化酶基因口GPase）无明显变化;组氨酸H3基因（HisH3）和己糖激酶I基因（胱,）在进入内休眠前有明显上升,蔗糖合酶基因（SuSy）则与之相反;尿苷二磷酸葡萄糖焦磷酸化酶（UGPase）表达总体上呈上调趋势,在进入内休眠后稍有下调。表明进入内休眠后,依赖HKl的糖信号转导途径起重要作用。在4℃处理后,与细胞分裂有关的基因HisH3含量急剧升高,而后下降,说明细胞分裂的减少并不是休眠期间抑制生长的原因;UGPase表现出与内休眠期一致的变化趋势,说明对低温有一定的适应性。     

脱落酸（ABA）诱导基因表达的调控元件

本文详细介绍了脱落酸（ABA）诱导诱导基因表达的各种调控元件及各调控元件间的相经作用和关系,综述了近年来对ABA诱导基因表达的调控元件的研究进展。     

脱落酸 (ABA)诱导基因表达的调控元件

本文详细介绍了脱落酸（ABA）诱导基因表达的各种调控元件及各调控元件间的相互作用和关系。综述了近年来对ABA诱导基因表达的调控元件的研究进展。     

Carbohydrate Metabolism by the Acetic Acid Bacteria

Vitamin requirements for the growth of the acetic acid bacteria were investigated extensively on a. taxonomical viewpoint and the following new findings were pointed out. Neither Acetobacter nor Intermediate strain required vitamin for the growth.

Gluconobacter required generally pantothenic acid. And some strains belonging to it did moreover somewhat of thiamine, nicotinic acid and p-aminobenzoic acid, although there was a difference of requirements between strains even in the same species. Riboflavin, pyridoxine, vitamin B₁₂, folic acid, biotin and inositol were unnecessary for the growth of the acetic acid bacteria. A taxonomical division of the acetic acid bacteria based on the vitamin requirements agreed well with that on basis of the oxidative activities for carbohydrates.     

Carbohydrate Metabolism by the Acetic Acid Bacteria

A general review of the acetic acid bacteria belonging to the intermediate type was accomplished physiologically, biochemically and morphologically. Conclusively, it was clarified that these were clearly a specific group and different from both Acetobacter and Gluconobacter, These were intermediate between lactaphilic and glycophilic, besides, on the carbohydrate oxidizability, these were intermediate between Acetobacter and Gluconobacter as mentioned previously.¹⁾ These showed the same result as Acetobacter on the vitamin requirement for the growth, but were closely related to Gluconobacter on the carbohydrate availability. And on the oxidative activity for amino acid, accompanying the deamination, these were also clearly distinguished from both Acetobacter and Gluconobacter, particularly these oxidized strongly l-serine. Differing from the observations by other investigators, these showed single flagellation, with the exception of multi-polar, but never multi-peritrichous.     

Effects of cis and trans Genetic Ancestry on Gene Expression in African Americans

Variation in gene expression is a fundamental aspect of human phenotypic variation. Several recent studies have analyzed gene expression levels in populations of different continental ancestry and reported population differences at a large number of genes. However, these differences could largely be due to non-genetic (e.g., environmental) effects. Here, we analyze gene expression levels in African American cell lines, which differ from previously analyzed cell lines in that individuals from this population inherit variable proportions of two continental ancestries. We first relate gene expression levels in individual African Americans to their genome-wide proportion of European ancestry. The results provide strong evidence of a genetic contribution to expression differences between European and African populations, validating previous findings. Second, we infer local ancestry (0, 1, or 2 European chromosomes) at each location in the genome and investigate the effects of ancestry proximal to the expressed gene (cis) versus ancestry elsewhere in the genome (trans). Both effects are highly significant, and we estimate that 12±3% of all heritable variation in human gene expression is due to cis variants.     

DNA Damage Responses in Prokaryotes: Regulating Gene Expression,Modulating Growth Patterns,and Manipulating Replication Forks

Recent advances in the area of bacterial DNA damage responses are reviewed here. The SOS pathway is still the major paradigm of bacterial DNA damage response, and recent studies have clarified the mechanisms of SOS induction and key physiological roles of SOS including a very major role in genetic exchange and variation. When considering diverse bacteria, it is clear that SOS is not a uniform pathway with one purpose, but rather a platform that has evolved for differing functions in different bacteria. Relating in part to the SOS response, the field has uncovered multiple apparent cell-cycle checkpoints that assist cell survival after DNA damage and remarkable pathways that induce programmed cell death in bacteria. Bacterial DNA damage responses are also much broader than SOS, and several important examples of LexA-independent regulation will be reviewed. Finally, some recent advances that relate to the replication and repair of damaged DNA will be summarized.Since the publication of DNA Repair and Mutagenesis in 2006 (Friedberg et al. 2006), our understanding of bacterial DNA damage responses has progressed significantly. Some studies have refined known pathways and filled in important details, whereas other studies have uncovered surprising new pathways such as bacterial programmed cell death and a form of replicative repair that reconstitutes severely shattered genomes. This review will focus on these recent advances, with only limited discussion and citation to work that precedes the 2006 tome.     

Gene Expression Profile Following Stable Expression of the Cellular Prion Protein

1. The cellular prion protein (PrPC) is expressed widely in neural and nonneural tissues at the highest level in neurons in the central nervous system (CNS).2. Recent studies indicated that transgenic mice with the cytoplasmic accumulation of PrPC exhibited extensive neurodegeneration in the cerebellum, although the underlying mechanism remains unknown. To identify the genes whose expression is controlled by overexpression of PrPC in human cells, we have established a stable PrPC-expressing HEK293 cell line designated P1 by the site-specific recombination technique.3. Microarray analysis identified 33 genes expressed differentially between P1 and the parent PrPC-non-expressing cell line among 12,814 genes examined. They included 18 genes involved in neuronal and glial functions, 5 related to production of extracellular matrix proteins, and 2 located in the complement cascade.4. Northern blot analysis verified marked upregulation in P1 of the brain-specific protein phosphatase 2A beta subunit (PPP2R2B), a causative gene of spinocerebellar ataxia 12, and the cerebellar degeneration-related autoantigen (CDR34) gene associated with development of paraneoplastic cerebellar degeneration.5. These results indicate that accumulation of PrPC in the cell caused aberrant regulation of a battery of the genes important for specific neuronal function. This represents a possible mechanism underlying PrPC-mediated selective neurodegeneration.