PnuC and the Utilization of the Nicotinamide Riboside Analog 3-Aminopyridine in Haemophilus influenzae

ABSTRACT The utilization pathway for the uptake of NAD and nicotinamide riboside was previously characterized for Haemophilus influenzae. We now report on the cellular location, topology, and substrate specificity of PnuC. pnuC of H. influenzae is only distantly related to pnuC of Escherichia coli and Salmonella enterica serovar Typhimurium. When E. coli PnuC was expressed in an H. influenzae pnuC mutant, it was able to take up only nicotinamide riboside and not nicotinamide mononucleotide. Therefore, we postulated that PnuC transporters in general possess specificity for nicotinamide riboside. Earlier studies showed that 3-aminopyridine derivatives (e.g., 3-aminopyridine adenine dinucleotide) are inhibitory for H. influenzae growth. By testing characterized strains with mutations in the NAD utilization pathway, we show that 3-aminopyridine riboside is inhibitory to H. influenzae and is taken up by the NAD-processing and nicotinamide riboside route. 3-Aminopyridine riboside is utilized effectively in a pnuC+ background. In addition, we demonstrate that 3-aminopyridine adenine dinucleotide resynthesis is produced by NadR. 3-Aminopyridine riboside-resistant H. influenzae isolates were characterized, and mutations in nadR could be detected. We also tested other species of the family Pasteurellaceae, Pasteurella multocida and Actinobacillus actinomycetemcomitans, and found that 3-aminopyridine riboside does not act as a growth inhibitor; hence, 3-aminopyridine riboside represents an anti-infective agent with a very narrow host range.

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NadN and e (P4) Are Essential for Utilization of NAD and Nicotinamide Mononucleotide but Not Nicotinamide Riboside in Haemophilus influenzae

Journal of Bacteriology ◽

10.1128/jb.183.13.3974-3981.2001 ◽

2001 ◽

Vol 183 (13) ◽

pp. 3974-3981 ◽

Cited By ~ 51

Author(s):

Gabriele Kemmer ◽

Thomas J. Reilly ◽

Joachim Schmidt-Brauns ◽

Gary W. Zlotnik ◽

Bruce A. Green ◽

...

Keyword(s):

Haemophilus Influenzae ◽

De Novo ◽

Factor V ◽

Nucleotidase Activity ◽

Nicotinamide Riboside ◽

Nicotinamide Mononucleotide ◽

Pathway Data ◽

Almost All

ABSTRACT Haemophilus influenzae has an absolute requirement for NAD (factor V) because it lacks almost all the biosynthetic enzymes necessary for the de novo synthesis of that cofactor. Factor V can be provided as either nicotinamide adenosine dinucleotide (NAD), nicotinamide mononucleotide (NMN), or nicotinamide riboside (NR) in vitro, but little is known about the source or the mechanism of uptake of these substrates in vivo. As shown by us earlier, at least two gene products are involved in the uptake of NAD, the outer membrane lipoprotein e (P4), which has phosphatase activity and is encoded by hel, and a periplasmic NAD nucleotidase, encoded by nadN. It has also been observed that the latter gene product is essential for H. influenzae growth on media supplemented with NAD. In this report, we describe the functions and substrates of these two proteins as they act together in an NAD utilization pathway. Data are provided which indicate that NadN harbors not only NAD pyrophosphatase but also NMN 5′-nucleotidase activity. Thee (P4) protein is also shown to have NMN 5′-nucleotidase activity, recognizing NMN as a substrate and releasing NR as its product. Insertion mutants of nadN or deletion and site-directed mutants of hel had attenuated growth and a reduced uptake phenotype when NMN served as substrate. Ahel and nadN double mutant was only able to grow in the presence of NR, whereas no uptake of NMN was observed.

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A Gene Encoding l-Methionine γ-Lyase Is Present in Enterobacteriaceae Family Genomes: Identification and Characterization of Citrobacter freundiil-Methionine γ-Lyase

Journal of Bacteriology ◽

10.1128/jb.187.11.3889-3893.2005 ◽

2005 ◽

Vol 187 (11) ◽

pp. 3889-3893 ◽

Cited By ~ 48

Author(s):

Ilya V. Manukhov ◽

Daria V. Mamaeva ◽

Sergei M. Rastorguev ◽

Nicolai G. Faleev ◽

Elena A. Morozova ◽

...

Keyword(s):

Shigella Flexneri ◽

Open Reading Frames ◽

Gene Encoding ◽

High Sequence Identity ◽

E Coli ◽

The Family ◽

Serovar Typhimurium ◽

Identification And Characterization ◽

Reading Frames

ABSTRACT Citrobacter freundii cells produce l-methionine γ-lyase when grown on a medium containing l-methionine. The nucleotide sequence of the hybrid plasmid with a C. freundii EcoRI insert of about 3.0 kbp contained two open reading frames, consisting of 1,194 nucleotides and 1,296 nucleotides, respectively. The first one (denoted megL) encoded l-methionine γ-lyase. The enzyme was overexpressed in Escherichia coli and purified. The second frame encoded a protein belonging to the family of permeases. Regions of high sequence identity with the 3′-terminal part of the C. freundii megL gene located in the same regions of Salmonella enterica serovar Typhimurium, Shigella flexneri, E. coli, and Citrobacter rodentium genomes were found.

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Untersuchungen zur aeroben bakteriellen Besiedlung der Vaginalschleimhaut klinisch gesunder Kätzinnen

Tierärztliche Praxis Ausgabe K Kleintiere / Heimtiere ◽

10.1055/s-0037-1622406 ◽

2004 ◽

Vol 32 (02) ◽

pp. 88-91

Author(s):

Susanne Kloß ◽

A. Wehrend ◽

Astrid König ◽

H. Bostedt

Keyword(s):

Staphylococcus Aureus ◽

Staphylococcus Epidermidis ◽

Pasteurella Multocida ◽

E Coli ◽

Klinische Relevanz ◽

Staphylococcus Intermedius

Zusammenfassung: Gegenstand und Ziel: Im Gegensatz zur Hündin liegen bei der Katze bisher wenige Studien über die genitale Keimflora geschlechtsgesunder Tiere vor. Ziel der Untersuchung war daher, physiologische Daten über die aerobe Vaginalflora bei dieser Spezies zu gewinnen. Material und Methoden: Für die vorliegende Studie standen 26 gesunde, anöstrische Katzen zur Verfügung, die zu einer Ovariohysterektomie vorgestellt wurden. Nach einer klinischen Untersuchung wurden von allen Probanden unter sterilen Bedingungen Vaginaltupfer entnommen. Ergebnisse: In allen Proben konnte ein Bakterienwachstum mit durchschnittlich zwei verschiedenen Bakterienspezies nachgewiesen werden. Die Gesamtkeimgehalte wurden bei 50% der Vaginaltupferproben als gering-, bei 15% als mittel- und bei 35% als hochgradig beurteilt. Vorherrschend waren Mischkulturen aus zwei bis vier verschiedenen Keimarten. Monokulturen wurden aus 38% der Tupferproben isoliert. Am häufigsten gelang der Nachweis von E. coli variatio haemolytica (E. coli var. haem.) (58%) und Staphylococcus epidermidis (42%). Als weitere Spezies wurden E. coli, α-, β-hämolysierende Streptokokken, anhämolysierende Streptokokken, aerobe Bazillen, Staphylococcus aureus, Staphylococcus intermedius, Pasteurella multocida sowie Klebsiellen isoliert. Auffällig ist die hohe Nachweisrate von E. coli var. haem. mit 35% in Mischkulturen und 23% in Reinkultur. Schlussfolgerungen: Die physiologische Mikroflora der felinen Vaginalschleimhaut differiert deutlich von der der anöstrischen Hündin. Besonders die Dominanz von E. coli var. haem. in 38% der Mischkulturen und 23% der Monokulturen bei der Katze ist hervorzuheben. Klinische Relevanz: Die vorliegenden Ergebnisse geben eine erste Grundlage für die Interpretation mikrobiologischer Befunde feliner Vaginaltupfer.

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Knowledge extraction for assisted curation of summaries of bacterial transcription factor properties

Database ◽

10.1093/database/baaa109 ◽

2020 ◽

Vol 2020 ◽

Author(s):

Carlos-Francisco Méndez-Cruz ◽

Antonio Blanchet ◽

Alan Godínez ◽

Ignacio Arroyo-Fernández ◽

Socorro Gama-Castro ◽

...

Keyword(s):

Transcriptional Regulation ◽

Knowledge Extraction ◽

Biomedical Literature ◽

Main Role ◽

E Coli ◽

Bacterial Transcription ◽

Manual Curation ◽

New Knowledge ◽

Serovar Typhimurium ◽

K 12

Abstract Transcription factors (TFs) play a main role in transcriptional regulation of bacteria, as they regulate transcription of the genetic information encoded in DNA. Thus, the curation of the properties of these regulatory proteins is essential for a better understanding of transcriptional regulation. However, traditional manual curation of article collections to compile descriptions of TF properties takes significant time and effort due to the overwhelming amount of biomedical literature, which increases every day. The development of automatic approaches for knowledge extraction to assist curation is therefore critical. Here, we show an effective approach for knowledge extraction to assist curation of summaries describing bacterial TF properties based on an automatic text summarization strategy. We were able to recover automatically a median 77% of the knowledge contained in manual summaries describing properties of 177 TFs of Escherichia coli K-12 by processing 5961 scientific articles. For 71% of the TFs, our approach extracted new knowledge that can be used to expand manual descriptions. Furthermore, as we trained our predictive model with manual summaries of E. coli, we also generated summaries for 185 TFs of Salmonella enterica serovar Typhimurium from 3498 articles. According to the manual curation of 10 of these Salmonella typhimurium summaries, 96% of their sentences contained relevant knowledge. Our results demonstrate the feasibility to assist manual curation to expand manual summaries with new knowledge automatically extracted and to create new summaries of bacteria for which these curation efforts do not exist. Database URL: The automatic summaries of the TFs of E. coli and Salmonella and the automatic summarizer are available in GitHub (https://github.com/laigen-unam/tf-properties-summarizer.git).

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Arabidopsis AtCNGC10 rescues potassium channel mutants of E. coli, yeast and Arabidopsis and is regulated by calcium/calmodulin and cyclic GMP in E. coli

Functional Plant Biology ◽

10.1071/fp04233 ◽

2005 ◽

Vol 32 (7) ◽

pp. 643 ◽

Cited By ~ 51

Author(s):

Xinli Li ◽

Tamás Borsics ◽

H. Michael Harrington ◽

David A. Christopher

Keyword(s):

Channel Blocker ◽

K Channel ◽

Structure Characteristic ◽

Dependent Manner ◽

Wild Type ◽

Yeast Saccharomyces Cerevisiae ◽

E Coli ◽

Diverse Species ◽

The Family ◽

Low K

We have isolated and characterised AtCNGC10, one of the 20 members of the family of cyclic nucleotide (CN)-gated and calmodulin (CaM)-regulated channels (CNGCs) from Arabidopsis thaliana (L.) Heynh. AtCNGC10 bound CaM in a C-terminal subregion that contains a basic amphiphillic structure characteristic of CaM-binding proteins and that also overlaps with the predicted CN-binding domain. AtCNGC10 is insensitive to the broad-range K+ channel blocker, tetraethylammonium, and lacks a typical K+-signature motif. However, AtCNGC10 complemented K+ channel uptake mutants of Escherichia coli (LB650), yeast (Saccharomyces cerevisiae CY162) and Arabidopsis (akt1-1). Sense 35S-AtCNGC10 transformed into the Arabidopsis akt1-1 mutant, grew 1.7-fold better on K+-limited medium relative to the vector control. Coexpression of CaM and AtCNGC10 in E. coli showed that Ca2+ / CaM inhibited cell growth by 40%, while cGMP reversed the inhibition by Ca2+ / CaM, in a AtCNGC10-dependent manner. AtCNGC10 did not confer tolerance to Cs+ in E. coli, however, it confers tolerance to toxic levels of Na+ and Cs+ in the yeast K+ uptake mutant grown on low K+ medium. Antisense AtCNGC10 plants had 50% less potassium than wild type Columbia. Taken together, the studies from three evolutionarily diverse species demonstrated a role for the CaM-binding channel, AtCNGC10, in mediating the uptake of K+ in plants.

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Gut Microbiota Prevents Sugar Alcohol-Induced Diarrhea

Nutrients ◽

10.3390/nu13062029 ◽

2021 ◽

Vol 13 (6) ◽

pp. 2029

Author(s):

Kouya Hattori ◽

Masahiro Akiyama ◽

Natsumi Seki ◽

Kyosuke Yakabe ◽

Koji Hase ◽

...

Keyword(s):

Gut Microbiota ◽

Gut Bacteria ◽

Food Science ◽

Sugar Alcohol ◽

Processed Food ◽

Phosphotransferase System ◽

Sugar Alcohols ◽

E Coli ◽

The Family ◽

Rdna Analysis

While poorly-absorbed sugar alcohols such as sorbitol are widely used as sweeteners, they may induce diarrhea in some individuals. However, the factors which determine an individual’s susceptibility to sugar alcohol-induced diarrhea remain unknown. Here, we show that specific gut bacteria are involved in the suppression of sorbitol-induced diarrhea. Based on 16S rDNA analysis, the abundance of Enterobacteriaceae bacteria increased in response to sorbitol consumption. We found that Escherichia coli of the family Enterobacteriaceae degraded sorbitol and suppressed sorbitol-induced diarrhea. Finally, we showed that the metabolism of sorbitol by the E. coli sugar phosphotransferase system helped suppress sorbitol-induced diarrhea. Therefore, gut microbiota prevented sugar alcohol-induced diarrhea by degrading sorbitol in the gut. The identification of the gut bacteria which respond to and degrade sugar alcohols in the intestine has implications for microbiome science, processed food science, and public health.

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Global versus Local Regulatory Roles for Lrp-Related Proteins: Haemophilus influenzae as a Case Study

Journal of Bacteriology ◽

10.1128/jb.183.13.4004-4011.2001 ◽

2001 ◽

Vol 183 (13) ◽

pp. 4004-4011 ◽

Cited By ~ 20

Author(s):

Devorah Friedberg ◽

Michael Midkiff ◽

Joseph M. Calvo

Keyword(s):

Amino Acid ◽

Haemophilus Influenzae ◽

Regulatory Protein ◽

Enteric Bacteria ◽

Regulatory Role ◽

Regulatory Function ◽

Ecological Niches ◽

E Coli ◽

Sequence Identity ◽

Related Proteins

ABSTRACT Lrp (leucine-responsive regulatory protein) plays a global regulatory role in Escherichia coli, affecting expression of dozens of operons. Numerous lrp-related genes have been identified in different bacteria and archaea, includingasnC, an E. coli gene that was the first reported member of this family. Pairwise comparisons of amino acid sequences of the corresponding proteins shows an average sequence identity of only 29% for the vast majority of comparisons. By contrast, Lrp-related proteins from enteric bacteria show more than 97% amino acid identity. Is the global regulatory role associated withE. coli Lrp limited to enteric bacteria? To probe this question we investigated LrfB, an Lrp-related protein fromHaemophilus influenzae that shares 75% sequence identity with E. coli Lrp (highest sequence identity among 42 sequences compared). A strain of H. influenzae having anlrfB null allele grew at the wild-type growth rate but with a filamentous morphology. A comparison of two-dimensional (2D) electrophoretic patterns of proteins from parent and mutant strains showed only two differences (comparable studies withlrp + and lrp E. coli strains by others showed 20 differences). The abundance of LrfB in H. influenzae, estimated by Western blotting experiments, was about 130 dimers per cell (compared to 3,000 dimers per E. colicell). LrfB expressed in E. coli replaced Lrp as a repressor of the lrp gene but acted only to a limited extent as an activator of the ilvIH operon. Thus, although LrfB resembles Lrp sufficiently to perform some of its functions, its low abundance is consonant with a more local role in regulating but a few genes, a view consistent with the results of the 2D electrophoretic analysis. We speculate that an Lrp having a global regulatory role evolved to help enteric bacteria adapt to their ecological niches and that it is unlikely that Lrp-related proteins in other organisms have a broad regulatory function.

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Synergistic action of E. coli endotoxin and Pasteurella multocida type A for the induction of bronchopneumonia in pigs

The Veterinary Journal ◽

10.1016/j.tvjl.2004.02.010 ◽

2005 ◽

Vol 169 (3) ◽

pp. 417-426 ◽

Cited By ~ 11

Author(s):

David J. Halloy ◽

Nathalie A. Kirschvink ◽

Jacques Mainil ◽

Pascal G. Gustin

Keyword(s):

Pasteurella Multocida ◽

Type A ◽

Synergistic Action ◽

E Coli

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An Improved Medium for Colistin Susceptibility Testing

Journal of Clinical Microbiology ◽

10.1128/jcm.01950-17 ◽

2018 ◽

Vol 56 (5) ◽

Cited By ~ 10

Author(s):

Konrad Gwozdzinski ◽

Saina Azarderakhsh ◽

Can Imirzalioglu ◽

Linda Falgenhauer ◽

Trinad Chakraborty

Keyword(s):

Susceptibility Testing ◽

Acquired Resistance ◽

Multidrug Resistant ◽

Colistin Resistance ◽

Reliable Determination ◽

Content Type ◽

E Coli ◽

Resistant Species ◽

Mueller Hinton ◽

Serovar Typhimurium

ABSTRACTThe plasmid-located colistin resistance genemcr-1confers low-level resistance to colistin, a last-line antibiotic against multidrug-resistant Gram-negative bacteria. Current CLSI-EUCAST recommendations require the use of a broth microdilution (BMD) method with cation-adjusted Mueller-Hinton (CA-MH) medium for colistin susceptibility testing, but approximately 15% of all MCR-1 producers are classified as sensitive in that broth. Here we report on an improved calcium-enhanced Mueller-Hinton (CE-MH) medium that permits simple and reliable determination ofmcr-1-containingEnterobacteriaceae. Colistin susceptibility testing was performed for 50mcr-1-containingEscherichia coliandKlebsiella pneumoniaeisolates, 7 intrinsically polymyxin-resistant species,K. pneumoniaeandE. coliisolates with acquired resistance to polymyxins due tomgrBandpmrBmutations, respectively, and 32mcr-1-negative, colistin-susceptible isolates ofAcinetobacter baumannii,Citrobacter freundii,Enterobacter cloacae,E. coli,K. pneumoniae, andSalmonella entericaserovar Typhimurium. A comparison of the colistin MICs determined in CA-MH medium and those obtained in CE-MH medium was performed using both the BMD and strip-based susceptibility test formats. We validated the data using an isogenic IncX4 plasmid lackingmcr-1. Use of the CE-MH broth provides clear separation between resistant and susceptible isolates in both BMD and gradient diffusion assays; this is true for bothmcr-1-containingEnterobacteriaceaeisolates and those exhibiting either intrinsic or acquired colistin resistance. CE-MH medium is simple to prepare and overcomes current problems associated with BMD and strip-based colistin susceptibility testing, and use of the medium is easy to implement in routine diagnostic laboratories, even in resource-poor settings.

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First Report of a Foodborne Salmonella enterica Serovar Gloucester (4:i:l,w) ST34 Strain Harboring blaCTX–M–55 and qnrS Genes Located in IS26-Mediated Composite Transposon

Frontiers in Microbiology ◽

10.3389/fmicb.2021.646101 ◽

2021 ◽

Vol 12 ◽

Author(s):

Lili Li ◽

Rikke Heidemann Olsen ◽

Anhua Song ◽

Jian Xiao ◽

Chong Wang ◽

...

Keyword(s):

Salmonella Enterica ◽

Structural Unit ◽

Bacterial Species ◽

Meat Products ◽

Sequence Type ◽

E Coli ◽

Serovar Typhimurium ◽

Long Read ◽

Phenotypic And Genotypic Characterization

Extended-spectrum β-lactamases (ESBLs) production and (fluoro)quinolone (FQ) resistance among Salmonella pose a public health threat. The objective of this study was the phenotypic and genotypic characterization of an ESBL-producing and nalidixic acid-resistant Salmonella enterica serovar Gloucester isolate (serotype 4:i:l,w) of sequence type 34 (ST34) from ready-to-eat (RTE) meat products in China. Whole-genome short and long read sequencing (HiSeq and MinION) results showed that it contained blaCTX–M–55, qnrS1, and tetB genes, with blaCTX–M–55 and qnrS1 located in chromosomal IS26-mediated composite transposon (IS26–qnrS1–IS3–Tn3–orf–blaCTX–M–55–ISEcp1–IS26). The same genetic structure was found in the chromosome of S. enterica subsp. enterica serovar Typhimurium strain and in several plasmids of Escherichia coli, indicating that the IS26-mediated composite transposon in the chromosome of S. Gloucester may originate from plasmids of E. coli and possess the ability to disseminate to Salmonella and other bacterial species. Besides, the structural unit qnrS1–IS3–Tn3–orf–blaCTX–M–55 was also observed to be linked with ISKpn19 in both the chromosomes and plasmids of various bacteria species, highlighting the contribution of the insertion sequences (IS26 and ISKpn19) to the co-dissemination of blaCTX–M–55 and qnrS1. To our knowledge, this is the first description of chromosomal blaCTX–M–55 and qnrS in S. Gloucester from RTE meat products. Our work expands the host range and provides additional evidence of the co-transfer of blaCTX–M–55 and qnrS1 among different species of Salmonella through the food chain.

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