Regulation of polar peptidoglycan biosynthesis by Wag31 phosphorylation in mycobacteria

Background. Sensing and responding to environmental changes is a central aspect of cell division regulation. Mycobacterium tuberculosis contains eleven Ser/Thr kinases, two of which, PknA and PknB, are key signaling molecules that regulate cell division/morphology. One substrate of these kinases is Wag31, and we previously showed that partial depletion of Wag31 caused morphological changes indicative of cell wall defects, and that the phosphorylation state of Wag31 affected cell growth in mycobacteria. In the present study, we further characterized the role of the Wag31 phosphorylation in polar peptidoglycan biosynthesis. Results. We demonstrate that the differential growth among cells expressing different wag31 alleles (wild-type, phosphoablative, or phosphomimetic) is caused by, at least in part, dissimilar nascent peptidoglycan biosynthesis. The phosphorylation state of Wag31 is found to be important for protein-protein interactions between the Wag31 molecules, and thus, for its polar localization. Consistent with these results, cells expressing a phosphomimetic wag31 allele have a higher enzymatic activity in the peptidoglycan biosynthetic pathway. Conclusions. The Wag31 Mtbphosphorylation is a novel molecular mechanism by which Wag31 Mtbregulates peptidoglycan synthesis and thus, optimal growth in mycobacteria. © 2010 Jani et al; licensee BioMed Central Ltd

DAYA DUKUNG DAN INDEKS DAYA DUKUNG HIJAUAN ALAMI DI AREAL PERKEBUNAN KELAPA DALAM SEBAGAI PAKAN TERNAK RUMINANSIA DI KECAMATAN TANIWEL KABUPATEN SERAM BAGIAN BARAT

The purpose of this study was to determine carrying capacity and carrying capacity index of natural forage as ruminant feed, and to determine botanical compositions and forage production in the coconut plantation area, District of Taniwel, Western Seram Regency. Primary and secondary data were collected, and data collection was conducted by using purposive sampling method. Variables measured included botanical composition, forage production, forage carrying capacity, and carrying capacity index of natural forage. The results showed that 64,81% of forage botanical composition was grass, 26,47% was weeds, and 10,52% was legumes. The carrying capacity of native forage in the coconut plantation area was 1.515 ruminants for fresh forage and 1.177 for forage dry matter, while carrying capacity index of native forage was 2 indicating unsafety level of forage available for ruminant feeding

PENGARUH PEMBERIAN EKSTRAK BAWANG PUTIH (ALIUM SATIVUM) TERHADAP TINGKAT KESEMBUHAN DAN KELULUSHIDUPAN KEPITING BAKAU (SCYLLA SERRATA) YANG DIMUTILASI

Abstract - This research aims to determine the effect of Garlic Extract and its maximum dosage on the healing rate and survival rate of mutilated mangrove crab. The method used in this study is laboratory experimental method using a complete randomized design with three treatments and three replications with extract concentration in treatment A (0.1%), treatment B (1%) and treatment C (10%). This research was conducted at the laboratory of the Faculty of Marine and Fisheries of Nusa Cendana University, Kupang. The results shows that the application of garlic extract (Alium sativum) have an effect on the healing rate and survival rate of mutilated mangrove crab with optimal garlic extract concentration of 10% is capable of killing the bacteria that attacked the mangrove crab (Scylla serrata). It is recommended for further research to use 10% concentration to cure and increase the life rate of the mutilated mangrove crab.    Keyword : Mangrove Crab, Mutilation, Garlic Extract.Abstrak - Penelitian ini betujuan untuk mengetahui adanya pengaruh pemberian ekstrak bawang putih dan  dosis yang optimal terhadap tingkat kesembuhan dan kelulushidupan kepiting bakau yang dimutilasi. Metode yang digunakan dalam penelitian ini adalah metode experimental laboratorium dengan menggunakan rancangan acak lengkap dengan tiga perlakuan dan tiga kali ulangan dengan konsentrasi ekstrak perlakuan A (0,1%), perlakuan B (1%) dan perlakuan C (10%) yang dilaksanakan di laboratoruim Fakultas Kelautan dan Perikanan Universitas Nusa Cendana kupang. Hasil penelitian menunjukkan bahwa pemberian ekstrak bawang putih (Alium sativum) berpengaruh terhadap tingkat kesembuhan dan kelulushidupan kepiting bakau yang dimutilasi dengan konsentrasi ekstrak bawang putih yang optimal 10% mampu membunuh bakteri yang menyerang kepiting bakau (Scylla serrata). Disarankan untuk melakukan penelitian lanjutan dengan menggunakan konsentrasi 10% untuk menyembuhkan dan meningkatkan kelulushidupan kepiting bakau yang dimutilasi. Kata kunci : Kepiting Bakau, Mutilasi, Ekstrak Bawang Puti

Fatty acid metabolism of Mycobacterium tuberculosis: a double-edged sword

Mycobacterium tuberculosis can cocatabolize a range of carbon sources. Fatty acids are among the carbons available inside the host’s macrophages. Here, we investigated the metabolic changes of the fatty acid-induced dormancy-like state of M. tuberculosis and its involvement in the acquisition of drug tolerance. We conducted metabolomics profiling using a phosphoenolpyruvate carboxykinase (PEPCK)-deficient M. tuberculosis strain in an acetate-induced dormancy-like state, highlighting an overaccumulation of methylcitrate cycle (MCC) intermediates that correlates with enhanced drug tolerance against isoniazid and bedaquiline. Further metabolomics analyses of two M. tuberculosis mutants, an ICL knockdown (KD) strain and PrpD knockout (KO) strain, each lacking an MCC enzyme—isocitrate lyase (ICL) and 2-methylcitrate dehydratase (PrpD), respectively—were conducted after treatment with antibiotics. The ICL KD strain, which lacks the last enzyme of the MCC, showed an overaccumulation of MCC intermediates and a high level of drug tolerance. The PrpD KO strain, however, failed to accumulate MCC intermediates as it lacks the second step of the MCC and showed only a minor level of drug tolerance compared to the ICL KD mutant and its parental strain (CDC1551). Notably, addition of authentic 2-methylisocitrate, an MCC intermediate, improved the M. tuberculosis drug tolerance against antibiotics even in glycerol medium. Furthermore, wild-type M. tuberculosis displayed levels of drug tolerance when cultured in acetate medium significantly greater than those in glycerol medium. Taken together, the fatty acid-induced dormancy-like state remodels the central carbon metabolism of M. tuberculosis that is functionally relevant to acquisition of M. tuberculosis drug tolerance

Driving performance analysis of the ACAS FOT data and recommendations for a driving workload manager

This project was performed under a subcontract to Delphi. The primary sponsor was the U.S. Dept. of Transportation, RSPA/Volpe National Transportation Sys. Ctr., 55 Broadway, Kendall Square, Cambridge, MA 02142.SAfety VEhicles using adaptive Interface Technology (SAVE-IT Project) Tasks 2 and 3This report contains analyses of driving performance data from the Advanced Collision Avoidance System (ACAS) Field Operational Test (FOT), with data from nearly 100 drivers and over 100,000 miles of driving. The analyses compared normal and distracted situations and determined thresholds that distinguish between maneuvering and non-maneuvering situations. Four questions were addressed: 1. How are measures of driver input (steering wheel angle, etc.) and vehicle output (heading, speed, etc.) distributed as a function of 4 road types [(a) ramps, (b) interstates and freeways, (c) arterials and minor arterials, and (d) collectors and local roads]? 2. What is the effect of the number of tasks on measures of driver performance as a function of road type? (The distributions for 0 and 1 tasks were similar. For 2 tasks, the range was sometimes 50% less.) 3. How well do linear thresholds distinguish between maneuvering and non-maneuvering situations, and what should those values be? (It varies with the threshold; sometimes the odds were 10:1. Other times they were 1:1.) 4. How effectively do steering and throttle entropy predict distracted and normal driving? (Only steering entropy showed any differences.)Delphi Delco Electronics Systemshttp://deepblue.lib.umich.edu/bitstream/2027.42/64468/1/102432.pd

Frequency of distracting tasks people do while driving: an analysis of the ACAS FOT data

SAfety VEhicles using adaptive Interface Technology (SAVE-IT Project)This report describes further analysis of data from the advanced collision avoidance system (ACAS) field operational test, a naturalistic driving study. To determine how distracted and nondistracted driving differ, a stratified sample of 2,914 video clips of the drivers’ faces and forward scene was coded to identify (1) where the driver was looking, (2) where their head was facing, (3) the secondary task performed, (4) what their hands were doing, and (5) the driving conditions. A sample of the clips from the first pass (balanced to equalize distracted and nondistracted clips) was examined frame by frame. Key findings include: 1. The most common secondary tasks were conversing, chewing gum, grooming, and using a cell phone, in that order. The most common subtasks were conversing on a cell phone, chewing gum, grooming with a hand, and biting one’s lips while chewing gum, in that order. 2. Depending on the analysis, 7 to 16% of all secondary tasks involved 2 or more secondary tasks occurring together, with 9 of the 10 most common combinations involving conversation or chewing gum. 3. Conversation tended to occur more frequently for older drivers and women, and on minor roads; and less often between midnight and 6:00 a.m., and when the outside temperature was below freezing. 4. Using the phone occurred more frequently for young drivers, for men, and in lighter traffic; and less often between midnight and 6:00 a.m.Delphi Delco Electronic Systemshttp://deepblue.lib.umich.edu/bitstream/2027.42/64457/1/102429.pd

How do distracted and normal driving differ: an analysis of the ACAS naturalistic driving data

SAfety VEhicles using adaptive Interface Technology (SAVE-IT Project)To determine how distracted and normal driving differ, this report re-examines driving performance data from the advanced collision avoidance system (ACAS) field operational test (FOT), a naturalistic driving study (96 drivers, 136,792 miles). In terms of overall driving performance statistics, distraction (defined as 4 successive video frames where the driver’s head was not oriented to the forward scene) had almost no effect, except for decreasing mean throttle opening by 36% and mean speed by 6%. No consistent normal/distracted differences were found in the parameters that fit the distributions of steering wheel angle, heading, and speed (all double exponential) and throttle opening (gamma) for each road type by driver age combination. In contrast, logistic regression identified other statistics and factors that discriminated between normal and distracted driving. They included (a) turn signal use and age group for expressways, (b) gender and if the lead vehicle range exceeded 60 m for major roads, and (c) lane width, lane offset, and lead vehicle velocity for minor roads. Finally, in a supplemental analysis, throttle holds (1 - 4 s periods of essentially no throttle change suggesting the driver may not be attending to driving) were actually more common for normal driving when a single time window (1 s) by threshold change combination (4 %) was selected. However, when settings (time windows of 1 – 4 s, thresholds of 1 – 4 %) were tailored for each age group by road class combination, throttle holds could identify when the driver was distracted.Delphi Delco Electronic Systemshttp://deepblue.lib.umich.edu/bitstream/2027.42/64458/1/102430.pd

Early mortality and primary causes of death in mothers of children with ID or ASD: a retrospective cohort study

INTRODUCTION: Mothers of children with intellectual disability or autism spectrum disorder (ASD) have poorer health than other mothers. Yet no research has explored whether this poorer health is reflected in mortality rates or whether certain causes of death are more likely. We aimed to calculate the hazard ratios for death and for the primary causes of death in mothers of children with intellectual disability or ASD compared to other mothers. METHODS: The study population comprised all mothers of live-born children in Western Australia from 1983-2005. We accessed state-wide databases which enabled us to link socio-demographic details, birth dates, diagnoses of intellectual disability or ASD in the children and dates and causes of death for all mothers who had died prior to 2011. Using Cox Regression with death by any cause and death by each of the three primary causes as the event of interest, we calculated hazard ratios for death for mothers of children intellectual disability or ASD compared to other mothers. RESULTS AND DISCUSSION: During the study period, mothers of children with intellectual disability or ASD had more than twice the risk of death. Mothers of children with intellectual disability were 40% more likely to die of cancer; 150% more likely to die of cardiovascular disease and nearly 200% more likely to die from misadventure than other mothers. Due to small numbers, only hazard ratios for cancer were calculated for mothers of children with ASD. These mothers were about 50% more likely to die from cancer than other mothers. Possible causes and implications of our results are discussed. CONCLUSION: Similar studies, pooling data from registries elsewhere, would improve our understanding of factors increasing the mortality of mothers of children with intellectual disability or ASD. This would allow the implementation of informed services and interventions to improve these mothers' longevity

Glutamate mediated metabolic neutralization mitigates propionate toxicity in intracellular Mycobacterium tuberculosis

Metabolic networks in biological systems are interconnected, such that malfunctioning parts can be corrected by other parts within the network, a process termed adaptive metabolism. Unlike Bacillus Calmette-Guérin (BCG), Mycobacterium tuberculosis (Mtb) better manages its intracellular lifestyle by executing adaptive metabolism. Here, we used metabolomics and identified glutamate synthase (GltB/D) that converts glutamine to glutamate (Q → E) as a metabolic effort used to neutralize cytoplasmic pH that is acidified while consuming host propionate carbon through the methylcitrate cycle (MCC). Methylisocitrate lyase, the last step of the MCC, is intrinsically downregulated in BCG, leading to obstruction of carbon flux toward central carbon metabolism, accumulation of MCC intermediates, and interference with GltB/D mediated neutralizing activity against propionate toxicity. Indeed, vitamin B12 mediated bypass MCC and additional supplement of glutamate led to selectively correct the phenotypic attenuation in BCG and restore the adaptive capacity of BCG to the similar level of Mtb phenotype. Collectively, a defective crosstalk between MCC and Q → E contributes to attenuation of intracellular BCG. Furthermore, GltB/D inhibition enhances the level of propionate toxicity in Mtb. Thus, these findings revealed a new adaptive metabolism and propose GltB/D as a synergistic target to improve the antimicrobial outcomes of MCC inhibition in Mtb

Metabolic adaptation of two in silico mutants of Mycobacterium tuberculosis during infection

ABSTRACT: Background: Up to date, Mycobacterium tuberculosis (Mtb) remains as the worst intracellular killer pathogen. To establish infection, inside the granuloma, Mtb reprograms its metabolism to support both growth and survival, keeping a balance between catabolism, anabolism and energy supply. Mtb knockouts with the faculty of being essential on a wide range of nutritional conditions are deemed as target candidates for tuberculosis (TB) treatment. Constraint-based genome-scale modeling is considered as a promising tool for evaluating genetic and nutritional perturbations on Mtb metabolic reprogramming. Nonetheless, few in silico assessments of the effect of nutritional conditions on Mtb’s vulnerability and metabolic adaptation have been carried out. Results: A genome-scale model (GEM) of Mtb, modified from the H37Rv iOSDD890, was used to explore the metabolic reprogramming of two Mtb knockout mutants (pfkA- and icl-mutants), lacking key enzymes of central carbon metabolism, while exposed to changing nutritional conditions (oxygen, and carbon and nitrogen sources). A combination of shadow pricing, sensitivity analysis, and flux distributions patterns allowed us to identify metabolic behaviors that are in agreement with phenotypes reported in the literature. During hypoxia, at high glucose consumption, the Mtb pfkA-mutant showed a detrimental growth effect derived from the accumulation of toxic sugar phosphate intermediates (glucose-6-phosphate and fructose-6-phosphate) along with an increment of carbon fluxes towards the reductive direction of the tricarboxylic acid cycle (TCA). Furthermore, metabolic reprogramming of the icl-mutant (icl1&icl2) showed the importance of the methylmalonyl pathway for the detoxification of propionyl-CoA, during growth at high fatty acid consumption rates and aerobic conditions. At elevated levels of fatty acid uptake and hypoxia, we found a drop in TCA cycle intermediate accumulation that might create redox imbalance. Finally, findings regarding Mtb-mutant metabolic adaptation associated with asparagine consumption and acetate, succinate and alanine production, were in agreement with literature reports. Conclusions: This study demonstrates the potential application of genome-scale modeling, flux balance analysis (FBA), phenotypic phase plane (PhPP) analysis and shadow pricing to generate valuable insights about Mtb metabolic reprogramming in the context of human granulomas