scholarly journals The Aspergillus nidulans xprF Gene Encodes a Hexokinase-like Protein Involved in the Regulation of Extracellular Proteases

Genetics ◽  
2000 ◽  
Vol 156 (4) ◽  
pp. 1559-1571 ◽  
Author(s):  
Margaret E Katz ◽  
Amir Masoumi ◽  
Stephen R Burrows ◽  
Carolyn G Shirtliff ◽  
Brian F Cheetham
Keyword(s):  
Sequence Analysis ◽  
Aspergillus Nidulans ◽  
Carbon Limitation ◽  
Extracellular Proteases ◽  
Nonsense Mutations ◽  
Acid Protein ◽  
Catalytic Role ◽  
New Type ◽  
Protease Deficient ◽  
A Minor

Abstract The extracellular proteases of Aspergillus nidulans are produced in response to limitation of carbon, nitrogen, or sulfur, even in the absence of exogenous protein. Mutations in the A. nidulans xprF and xprG genes have been shown to result in elevated levels of extracellular protease in response to carbon limitation. The xprF gene was isolated and sequence analysis indicates that it encodes a 615-amino-acid protein, which represents a new type of fungal hexokinase or hexokinase-like protein. In addition to their catalytic role, hexokinases are thought to be involved in triggering carbon catabolite repression. Sequence analysis of the xprF1 and xprF2 alleles showed that both alleles contain nonsense mutations. No loss of glucose or fructose phosphorylating activity was detected in xprF1 or xprF2 mutants. There are two possible explanations for this observation: (1) the xprF gene may encode a minor hexokinase or (2) the xprF gene may encode a protein with no hexose phosphorylating activity. Genetic evidence suggests that the xprF and xprG genes are involved in the same regulatory pathway. Support for this hypothesis was provided by the identification of a new class of xprG- mutation that suppresses the xprF1 mutation and results in a protease-deficient phenotype.

scholarly journals A p53-like transcription factor similar to Ndt80 controls the response to nutrient stress in the filamentous fungus, Aspergillus nidulans

F1000Research ◽  
2013 ◽  
Vol 2 ◽  
pp. 72 ◽  
Author(s):  
Margaret E Katz ◽  
Kathryn Braunberger ◽  
Gauncai Yi ◽  
Sarah Cooper ◽  
Heather M Nonhebel ◽  
...  
Keyword(s):  
Aspergillus Nidulans ◽  
Transcriptional Profiling ◽  
Nutrient Stress ◽  
Nutrient Sensing ◽  
Carbon Limitation ◽  
Nutrient Depletion ◽  
Null Mutant ◽  
Global Regulator ◽  
Extracellular Proteases ◽  
Number Of Genes

TheAspergillus nidulans xprGgene encodes a putative transcriptional activator that is a member of the Ndt80 family in the p53-like superfamily of proteins. Previous studies have shown that XprG controls the production of extracellular proteases in response to starvation. We undertook transcriptional profiling to investigate whether XprG has a wider role as a global regulator of the carbon nutrient stress response. Our microarray data showed that the expression of a large number of genes, including genes involved in secondary metabolism, development, high-affinity glucose uptake and autolysis, were altered in anxprGΔnull mutant. Many of these genes are known to be regulated in response to carbon starvation. We confirmed that sterigmatocystin and penicillin production is reduced inxprG-mutants. The loss of fungal mass and secretion of pigments that accompanies fungal autolysis in response to nutrient depletion was accelerated in anxprG1gain-of-function mutant and decreased or absent in anxprG-mutant. The results support the hypothesis that XprG plays a major role in the response to carbon limitation and that nutrient sensing may represent one of the ancestral roles for the p53-like superfamily. Disruption of the AN6015 gene, which encodes a second Ndt80-like protein, showed that it is required for sexual reproduction inA. nidulans.

scholarly journals Complete Genome Sequence of Bacillus subtilis Strain WB800N, an Extracellular Protease-Deficient Derivative of Strain 168

2018 ◽  
Vol 7 (18) ◽  
Author(s):  
Haeyoung Jeong ◽  
Da-Eun Jeong ◽  
Seung-Hwan Park ◽  
Seong Joo Kim ◽  
Soo-Keun Choi
Keyword(s):  
Bacillus Subtilis ◽  
Genome Sequence ◽  
Complete Genome Sequence ◽  
Complete Genome ◽  
Genetically Engineered ◽  
Subtilis Strain ◽  
Secretory Proteins ◽  
Extracellular Proteases ◽  
Content Type ◽  
Protease Deficient

Bacillus subtilis WB800N is a genetically engineered variant of B. subtilis 168, such that all extracellular proteases are disrupted, which enables WB800N to be widely used for the expression of secretory proteins. Here, we report the 4.2-Mb complete genome sequence of WB800N and present all of the disrupted gene structure.

scholarly journals A Minor Innovation in Constructing a Small Bowel Stoma in Neonates with Small Bowel Atresia to Reduce the Morbidity

2016 ◽  
Vol 5 (4) ◽  
pp. 45 ◽  
Author(s):  
Naeem Khan ◽  
Saba Bakht ◽  
Nadia Zaheer
Keyword(s):  
Small Bowel ◽  
Primary Anastomosis ◽  
Intestinal Atresia ◽  
Stoma Formation ◽  
New Type ◽  
Small Bowel Atresia ◽  
Bowel Atresia ◽  
A Minor ◽  
Lost To Follow Up

Background: Intestinal atresia has still significant morbidity in developing countries. Stomas are now not recommended in every case of intestinal atresia; primary anastomosis is the goal of surgery after resection of dilated adynamic gut. A new type of stoma formation along with primary anastomosis is being presented here.Materials and Methods: This report is based on our experience of many cases with this technique in last 12 years but all the details and long follow-up of each case is not available. However the method of surgical procedure, progress, complications, and advantages encountered have been highlighted.Results: Presently we have data of 7 patients; others are lost to follow up. Three had died with other associated problems, namely one with multiple atresias, two with septic shock and prematurity. Two stomas did not require formal closure because stoma shriveled and disappeared. Two other stomas had grown very long like a diverticulum when these were closed after 5 and 8 months.Conclusion: This technique is another attempt to decrease morbidity of patients of intestinal atresia especially in those cases where short bowel syndrome is feared after resection of proximal dilated gut.

scholarly journals Formation Mechanisms of Snow Crystals at Low Temperature

1985 ◽  
Vol 6 ◽  
pp. 232-234 ◽  
Author(s):  
Noboru Sato ◽  
Katsuhiro Kikuchi
Keyword(s):  
Water Saturation ◽  
Diffusion Chamber ◽  
Formation Mechanisms ◽  
Polar Regions ◽  
Maximum Frequency ◽  
Growth Mechanisms ◽  
New Type ◽  
Number Frequency ◽  
Snow Crystals ◽  
A Minor

To study crystal shapes, and formation and growth mechanisms of snow crystals formed below -20 °C, a new type of diffusion chamber was constructed. Using this chamber, different kinds of “peculiar shaped” crystals previously observed in nature have been produced, together with normal types of snow crystals. Gohei twins, one of the most typical polycrystalline shapes in nature, have been produced artificially. The vapor pressure was at or near water saturation at the time of nucleation. Analysis of photomicrographs and replicas of Gohei twins that were replicated in the polar regions show that the number frequency of the tip angle has a maximum frequency at about 77° and a minor one at about 54°.On the basis of these results, a formation mechanism for some Gohei twins is proposed in this paper.

Bioinformatics Analysis and Characteristics of US2 Protein Encoded by the Newly Identified US2 Gene of Duck Enteritis Virus

2012 ◽  
Vol 424-425 ◽  
pp. 493-497
Author(s):  
Jie Gao ◽  
An Chun Cheng ◽  
Ming Shu Wang
Keyword(s):  
Amino Acids ◽  
Sequence Analysis ◽  
Protein Sequence ◽  
Bioinformatics Analysis ◽  
Functional Study ◽  
Protein Sequence Analysis ◽  
Tegument Proteins ◽  
The Us ◽  
New Type ◽  
Enteritis Virus

In this article,we intend to provide readers with some bioinformation of DEV Us2 protein,for little information of this protein has been cited online.Us2 protein encoded by the DEV-US2 gene is one of the DEV tegument proteins. Like most members of the alphaherpesvirinae,the genes in the US region of its genome are well conserved,which means that both the major DEV protein Us2 and alphaherpesvirinae protein Us2 possess the similar functions.Us2 protein sequence analysis indicates that the protein possesses typical characteristics of tegument protein.The precursor Us2 consists of 239 amino acids and exhibits a molecular mass of 34 kDa. In conclusion,all the datas and consequences will provide a basis for further functional study of the DEV-Us2 protein and provide necessary datas for the new type clinical diagnosis of DEV and the development of new DEV vaccine.

Two novel metal-independent long-chain alkyl alcohol dehydrogenases from Geobacillus thermodenitrificans NG80-2

Microbiology ◽  
2009 ◽  
Vol 155 (6) ◽  
pp. 2078-2085 ◽  
Author(s):  
Xueqian Liu ◽  
Yanpeng Dong ◽  
Jing Zhang ◽  
Aixiang Zhang ◽  
Lei Wang ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Sequence Analysis ◽  
Isopropyl Alcohol ◽  
Geobacillus Thermodenitrificans ◽  
Assay Condition ◽  
Alcohol Dehydrogenases ◽  
Adh Genes ◽  
New Type ◽  
Long Chain

Two alkyl alcohol dehydrogenase (ADH) genes from the long-chain alkane-degrading strain Geobacillus thermodenitrificans NG80-2 were characterized in vitro. ADH1 and ADH2 were prepared heterologously in Escherichia coli as a homooctameric and a homodimeric protein, respectively. Both ADHs can oxidize a broad range of alkyl alcohols up to at least C30, as well as 1,3-propanediol and acetaldehyde. ADH1 also oxidizes glycerol, and ADH2 oxidizes isopropyl alcohol, isoamylol, acetone, octanal and decanal. The best substrate is ethanol for ADH1 and 1-octanol for ADH2. For both ADHs, the optimum assay condition is at 60 °C and pH 8.0, and both NAD and NADP can be used as the cofactor. Sequence analysis reveals that ADH1 and ADH2 belong to the Fe-containing/activated long-chain ADHs. However, the two enzymes contain neither Fe nor other metals, and Fe is not required for the activity, suggesting a new type of ADH. The ADHs characterized here are potentially useful in crude oil bioremediation and other bioconversion processes.

Analysis of Two Aspergillus nidulans Genes Encoding Extracellular Proteases

2000 ◽  
Vol 29 (3) ◽  
pp. 201-210 ◽  
Author(s):  
Patricia A vanKuyk ◽  
Brian F Cheetham ◽  
Margaret E Katz
Keyword(s):  
Aspergillus Nidulans ◽  
Extracellular Proteases ◽  
Genes Encoding

scholarly journals Extracellular Pneumococcal Serine Proteases Affect Nasopharyngeal Colonization

2021 ◽  
Vol 10 ◽  
Author(s):  
Murtadha Q. Ali ◽  
Thomas P. Kohler ◽  
Gerhard Burchhardt ◽  
Andreas Wüst ◽  
Nadin Henck ◽  
...  
Keyword(s):  
Serine Proteases ◽  
Bacterial Load ◽  
Acute Infection ◽  
Minor Role ◽  
Extracellular Proteases ◽  
Nasopharyngeal Colonization ◽  
Invasive Diseases ◽  
Pneumococcal Colonization ◽  
A Minor ◽  
The Impact

Streptococcus pneumoniae has evolved versatile strategies to colonize the nasopharynx of humans. Colonization is facilitated by direct interactions with host cell receptors or via binding to components of the extracellular matrix. In addition, pneumococci hijack host-derived extracellular proteases such as the serine protease plasmin(ogen) for ECM and mucus degradation as well as colonization. S. pneumoniae expresses strain-dependent up to four serine proteases. In this study, we assessed the role of secreted or cell-bound serine proteases HtrA, PrtA, SFP, and CbpG, in adherence assays and in a mouse colonization model. We hypothesized that the redundancy of serine proteases compensates for the deficiency of a single enzyme. Therefore, double and triple mutants were generated in serotype 19F strain EF3030 and serotype 4 strain TIGR4. Strain EF3030 produces only three serine proteases and lacks the SFP encoding gene. In adherence studies using Detroit-562 epithelial cells, we demonstrated that both TIGR4Δcps and 19F mutants without serine proteases or expressing only CbpG, HtrA, or PrtA have a reduced ability to adhere to Detroit-562 cells. Consistent with these results, we show that the mutants of strain 19F, which preferentially colonizes mice, abrogate nasopharyngeal colonization in CD-1 mice after intranasal infection. The bacterial load in the nasopharynx was monitored for 14 days. Importantly, mutants showed significantly lower bacterial numbers in the nasopharynx two days after infection. Similarly, we detected a significantly reduced pneumococcal colonization on days 3, 7, and 14 post-inoculations. To assess the impact of pneumococcal serine proteases on acute infection, we infected mice intranasally with bioluminescent and invasive TIGR4 or isogenic triple mutants expressing only CbpG, HtrA, PrtA, or SFP. We imaged the acute lung infection in real-time and determined the survival of the mice. The TIGR4lux mutant expressing only PrtA showed a significant attenuation and was less virulent in the acute pneumonia model. In conclusion, our results showed that pneumococcal serine proteases contributed significantly to pneumococcal colonization but played only a minor role in pneumonia and invasive diseases. Because colonization is a prerequisite for invasive diseases and transmission, these enzymes could be promising candidates for the development of antimicrobials to reduce pneumococcal transmission.

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