AC2DGel: analysis and comparison of 2D gels

Two-dimensional gel electrophoresis can retrieve information regarding thousands of different proteins from a crude protein sample. One of the major challenges in field of proteomics is to extract maximum information from 2D gels. In this study, we developed a web server for the analysis and comparison of 2D gels, which consists of three major modules. The first module allows the analysis of gels on the basis of molecular weight and pH. This module assists in calculating molecular weight and pH of a protein by clicking on corresponding spot at 2D gel image. The second module allows the comparison of two gels and presents the result as a superimposed image where spots/proteins on two gels can be examined. The useful feature of this module is that it allows the comparison of whole gel images or user specified areas or spots of gels. Besides this, it also allows zooming and other image transformations such as brightness and contract enhancement. The third module is an interface to the database of 2-D gel images maintained locally. The database consists of information about more than 3500 well annotated 2-D gel images obtained from public databases and literature. The server allows searching of gels from the database by keyword. Web server AC2Dgel is available for public from http://www1.imtech.res.in/raghava/ac2dgel/

Combined Transcriptomic and Proteomic Profiling of E. coli under Microaerobic versus Aerobic Conditions: The Multifaceted Roles of Noncoding Small RNAs and Oxygen-Dependent Sensing in Global Gene Expression Control

Adaptive mechanisms that facilitate intestinal colonization by the human microbiota, including Escherichia coli, may be better understood by analyzing the physiology and gene expression of bacteria in low-oxygen environments. We used high-throughput transcriptomics and proteomics to compare the expression profiles of E. coli grown under aerobic versus microaerobic conditions. Clustering of high-abundance transcripts under microaerobiosis highlighted genes controlling acid-stress adaptation (gadAXW, gadAB, hdeAB-yhiD and hdeD operons), cell adhesion/biofilm formation (pgaABCD and csgDEFG operons), electron transport (cydAB), oligopeptide transport (oppABCDF), and anaerobic respiration/fermentation (hyaABCDEF and hycABCDEFGHI operons). In contrast, downregulated genes were involved in iron transport (fhuABCD, feoABC and fepA-entD operons), iron-sulfur cluster assembly (iscRSUA and sufABCDSE operons), aerobic respiration (sdhDAB and sucABCDSE operons), and de novo nucleotide synthesis (nrdHIEF). Additionally, quantitative proteomics showed that the products (proteins) of these high- or low-abundance transcripts were expressed consistently. Our findings highlight interrelationships among energy production, carbon metabolism, and iron homeostasis. Moreover, we have identified and validated a subset of differentially expressed noncoding small RNAs (i.e., CsrC, RyhB, RprA and GcvB), and we discuss their regulatory functions during microaerobic growth. Collectively, we reveal key changes in gene expression at the transcriptional and post-transcriptional levels that sustain E. coli growth when oxygen levels are low.Ministry of Science and Technology, Taiwan: 104-2311-B-001-011-MY3, and 107-2311-B-001-029-MY3; Academia Sinica: AS 2323, and AS-IA-110-L0

Representation of functional information in the SWISS-PROT data bank

Functional information in SWISS-PROT results, primarily, from assessment of articles reporting characterization. Predicted information is labeled with flags describing the evidence level (e.g. potential, probable, by similarity)

Representation of functional information in the SWISS-PROT Data Bank

Summary: Functional information in SWISS-PROT results, primarily, from assessment of articles reporting characterization. Predicted information is labeled with flags describing the evidence level (e.g. potential, probable, by similarity). Availability: SWISS-PROT can be accessed via http://www.expasy.ch/sprotand http://www.ebi.ac.uk/swissprot/ Contact: [email protected]