Membrane protein structures enter an exponential growth phase

1AbstractAn automated statistical and error analysis of 45 countries or regions with more than 1000 cases of COVID-19 as of March 28, 2020, has been performed. This study reveals differences in the rate of disease spreading rate over time in different countries. This survey observes that most countries undergo a beginning exponential growth phase, which transitions into a power-law phase, as recently suggested by Ziff and Ziff. Tracking indicators of growth, such as the power-law exponent, are a good indication of the relative danger different countries are in and show when social measures are effective towards slowing the spread. The data compiled here are usefully synthesizing a global picture, identifying country to country variation in spreading, and identifying countries most at risk. This analysis may factor into how best to track the effectiveness of social distancing policies and quarantines in real-time as data is updated each day.

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Biosynthesis and turnover of outer-membrane proteins in Escherichia coli ML308-225

Biochemical Journal ◽

10.1042/bj1820407 ◽

1979 ◽

Vol 182 (2) ◽

pp. 407-412 ◽

Cited By ~ 3

Author(s):

R J Allen ◽

G K Scott

Keyword(s):

Escherichia Coli ◽

Protein Synthesis ◽

Outer Membrane ◽

Bacterial Growth ◽

Growth Phase ◽

Exponential Growth ◽

Outer Membrane Proteins ◽

Exponential Growth Phase ◽

Outer Membranes ◽

Dilution Experiments

Isolated outer membranes and outer-membrane extracts from Escherichia coli ML308-225 in the early-exponential growth phase contain more protein than do corresponding preparations from late-exponential- or stationary-phase bacteria. Isotope-dilution experiments show that this is due to a loss of protein from the membrane during the exponential growth phase. Inhibition of bacterial growth and protein synthesis stabilizes the outer-membrane-protein concentration. Protein synthesis in the absence of bacterial growth results in higher concentrations of protein in the outer membrane.

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Exponential growth phase ofPseudomonas methanolica batch cultures

Zeitschrift für allgemeine Mikrobiologie ◽

10.1002/jobm.3630130610 ◽

1973 ◽

Vol 13 (6) ◽

pp. 523-528 ◽

Cited By ~ 1

Author(s):

E. M. Shulgovskaya ◽

I. I. Ivanova ◽

G. G. Sotnicov

Keyword(s):

Growth Phase ◽

Exponential Growth ◽

Exponential Growth Phase ◽

Batch Cultures

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The Putrescine Importer PuuP of Escherichia coli K-12

Journal of Bacteriology ◽

10.1128/jb.01314-08 ◽

2009 ◽

Vol 191 (8) ◽

pp. 2776-2782 ◽

Cited By ~ 36

Author(s):

Shin Kurihara ◽

Yuichi Tsuboi ◽

Shinpei Oda ◽

Hyeon Guk Kim ◽

Hidehiko Kumagai ◽

...

Keyword(s):

Escherichia Coli ◽

Gene Cluster ◽

Growth Phase ◽

Exponential Growth ◽

Minimal Medium ◽

Exponential Growth Phase ◽

E Coli ◽

Genes Encoding ◽

K 12 ◽

Utilization Pathway

ABSTRACT The Puu pathway is a putrescine utilization pathway involving gamma-glutamyl intermediates. The genes encoding the enzymes of the Puu pathway form a gene cluster, the puu gene cluster, and puuP is one of the genes in this cluster. In Escherichia coli, three putrescine importers, PotFGHI, PotABCD, and PotE, were discovered in the 1990s and have been studied; however, PuuP had not been discovered previously. This paper shows that PuuP is a novel putrescine importer whose kinetic parameters are equivalent to those of the polyamine importers discovered previously. A puuP + strain absorbed up to 5 mM putrescine from the medium, but a ΔpuuP strain did not. E. coli strain MA261 has been used in previous studies of polyamine transporters, but PuuP had not been identified previously. It was revealed that the puuP gene of MA261 was inactivated by a point mutation. When E. coli was grown on minimal medium supplemented with putrescine as the sole carbon or nitrogen source, only PuuP among the polyamine importers was required. puuP was expressed strongly when putrescine was added to the medium or when the puuR gene, which encodes a putative repressor, was deleted. When E. coli was grown in M9-tryptone medium, PuuP was expressed mainly in the exponential growth phase, and PotFGHI was expressed independently of the growth phase.

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Functional elucidation of the non-coding RNAs of Kluyveromyces marxianus in the exponential growth phase

BMC Genomics ◽

10.1186/s12864-016-2474-z ◽

2016 ◽

Vol 17 (1) ◽

Cited By ~ 1

Author(s):

Yoo-Bok Cho ◽

Eun Ju Lee ◽

Suhyung Cho ◽

Tae Yong Kim ◽

Jin Hwan Park ◽

...

Keyword(s):

Growth Phase ◽

Exponential Growth ◽

Kluyveromyces Marxianus ◽

Exponential Growth Phase ◽

Non Coding Rnas

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Giardia lamblia: axenic growth in autoclaved and filtered Diamond's TYI-S-33 medium

Canadian Journal of Zoology ◽

10.1139/z82-219 ◽

1982 ◽

Vol 60 (7) ◽

pp. 1673-1675 ◽

Cited By ~ 12

Author(s):

M. Belosevic ◽

G. M. Faubert ◽

N. A. Croll ◽

J. D. MacLean

Keyword(s):

Growth Phase ◽

Exponential Growth ◽

Giardia Lamblia ◽

Culture Medium ◽

Exponential Growth Phase ◽

Growth Studies ◽

Generation Times ◽

The Mean ◽

Axenic Growth

The trophozoites of Giardia lamblia were gradually adapted to grow in both autoclaved and filtered Diamond's TYI-S-33 culture medium. Comparative growth studies indicated that the growth of organisms was significantly higher in filtered TYI-S-33 medium. In both types of media the exponential growth phase occurred between 48 and 96 h postinoculation. The mean number of trophozoites at 96 h was 1.94 × 105 and 4.82 × 105 cells/mL for autoclaved and filtered media, respectively. The generation times for the exponential growth phase were 9.66 h. for autoclaved and 7.69 h for filtered medium. The percentage of dead trophozoites was similar in both media and was 14% for the first 8 days postinoculation.

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Elevated acetyl-CoA by amino acid recycling fuels microalgal neutral lipid accumulation in exponential growth phase for biofuel production

Plant Biotechnology Journal ◽

10.1111/pbi.12648 ◽

2016 ◽

Vol 15 (4) ◽

pp. 497-509 ◽

Cited By ~ 13

Author(s):

Lina Yao ◽

Hui Shen ◽

Nan Wang ◽

Jaspaul Tatlay ◽

Liang Li ◽

...

Keyword(s):

Amino Acid ◽

Neutral Lipid ◽

Growth Phase ◽

Exponential Growth ◽

Lipid Accumulation ◽

Biofuel Production ◽

Exponential Growth Phase ◽

Acetyl Coa

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Variability of neuD transcription levels and capsular sialic acid expression among serotype III group B Streptococcus strains

Microbiology ◽

10.1099/mic.0.050013-0 ◽

2011 ◽

Vol 157 (12) ◽

pp. 3282-3291 ◽

Cited By ~ 2

Author(s):

Marie-Frédérique Lartigue ◽

Agnès Fribourg Poulard ◽

Rim Al Safadi ◽

Hélène Pailhories ◽

Anne-Sophie Domelier-Valentin ◽

...

Keyword(s):

Genetic Diversity ◽

Sialic Acid ◽

Growth Phase ◽

Exponential Growth ◽

Bacterial Species ◽

Group B Streptococcus ◽

Neonatal Meningitis ◽

Exponential Growth Phase ◽

Growth Phases ◽

Group B

Serotype III group B Streptococcus (GBS) is the major cause of neonatal meningitis, but the risk of infection in the colonized neonates is variable. Capsular sialic acid (Sia), whose synthesis is encoded by neu genes, appears to be a major virulence factor in several bacterial species able to reach the cerebrospinal fluid. Therefore, variations of Sia expression related to the genetic diversity of strains may have an impact on the risk of meningitis in colonized neonates. We characterized by MLST the phylogenetic diversity of 64 serotype III GBS strains isolated from vaginal flora and randomly selected. These strains mostly belonged to three major sequence types (STs): ST1 (11 %), ST17 (39 %) and ST19 (31 %). The genetic diversity of strains of these lineages, characterized by PFGE, allowed the selection of 17 representative strains, three ST1, six ST17 and eight ST19, with NEM316 as reference, in order to evaluate (i) by quantitative RT-PCR, the level of transcription of the neuD gene as a marker for the transcription of neu genes and (ii) by enzymological analysis, the expression of Sia. The mean transcription level of neuD was higher for ST17 strains than for ST1 and ST19 strains in the early, mid- and late exponential growth phases, and was maximum in the early exponential growth phase for ST17 strains and in the mid-exponential growth phase for ST1 and ST19 strains. Mean Sia concentration was higher for ST17 than for ST1 and ST9 strains in all three growth phases. For the total population, Sia concentration varied notably in the stationary phase, from 0.38 to 9.30 nmol per 108 viable bacteria, with a median value of 2.99 nmol per 108 bacteria. All ST17 strains, only one-third of the ST19 strains and none of the ST1 strains had Sia concentrations higher than the median Sia concentration. Therefore, differences in the level of expression of Sia by strains of the major serotype III GBS phylogenetic lineages might be one of the factors that explain the leading role of ST17 strains in neonatal meningitis.

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