scholarly journals Metabolic profiling reveals nutrient preferences during carbon utilization in Bacillus species

2020 ◽  
Author(s):  
James D. Chang ◽  
Ellen E. Vaughan ◽  
Carmen Gu Liu ◽  
Joseph W. Jelinski ◽  
Austen L. Terwilliger ◽  
...  
Keyword(s):  
Staphylococcus Aureus ◽  
Pathogenic Bacteria ◽  
Bacterial Species ◽  
Bacillus Species ◽  
Ecological Niches ◽  
Phenotype Microarray ◽  
Human Pathogens ◽  
Carbon Utilization ◽  
Reducing Equivalents

AbstractPathogenic bacteria take host nutrients to support their growth, division, survival, and pathogenesis. The genus Bacillus includes species with diverse natural histories, including free-living nonpathogenic heterotrophs such as B. subtilis and host-dependent pathogens such as B. anthracis (the etiological agent of the disease anthrax) and B. cereus, a cause of food poisoning. Although highly similar genotypically, the ecological niches of these three species are mutually exclusive, which raises the untested hypothesis that their metabolism has speciated along a nutritional tract. Here, we employed a quantitative measurement of the number of reducing equivalents as a function of growth on hundreds of different sources of carbon to gauge the “culinary preferences” of three distinct Bacillus species, and related Staphylococcus aureus. We show that each species had widely varying metabolic ability to utilize diverse sources of carbon that correlated to their ecological niches. In addition, carbohydrates are shown to be the preferred sources of carbon when grown under ideal in vitro conditions. Rather unexpectedly, these metabolic utilizations did not correspond one-to-one with an increase in biomass, which brings to question what cellular activity should be considered productive when it comes to virulence. Finally, we applied this system to the growth and survival of B. anthracis in a blood-based environment and find that amino acids become the preferred source of energy while demonstrating the possibility of applying this approach to identifying xenobiotics or host compounds that can promote or interfere with bacterial metabolism during infection.Author summarySuccessful organisms must make nutritional adaptations to thrive in their environment. Bacterial pathogens are no exception, having evolved for survival inside their hosts. The host combats these pathogens by depriving them of potential biochemical resources, termed nutritional immunity. This places pathogens under pressure to utilize their resources efficiently and strategically, and their metabolism must in turn be tailored for this situation. In this study, we examined the carbon metabolism of three human pathogens of varying virulence (Bacillus anthracis, Bacillus cereus, and Staphylococcus aureus) and one nonpathogenic Bacillus (Bacillus subtilis) via a phenotype microarray that senses reducing equivalents produced during metabolism. Our analysis shows the existence of distinct preferences by these pathogens towards only a select few carbohydrates and implies reliance on specific metabolic pathways. These metabolic signatures obtained could be distinguished from one bacterial species to another, and we conclude that nutrient preferences offer a new perspective into investigating how pathogens can thrive during infection despite host-induced starvation.

scholarly journals Discovery and Characterization of Low-Molecular Weight Inhibitors of Erwinia tracheiphila

2020 ◽  
Vol 110 (5) ◽  
pp. 989-998
Author(s):  
Cláudio M. Vrisman ◽  
Loïc Deblais ◽  
Yosra A. Helmy ◽  
Reed Johnson ◽  
Gireesh Rajashekara ◽  
...  
Keyword(s):  
Pseudomonas Syringae ◽  
High Throughput Screening ◽  
Pathogenic Bacteria ◽  
Bacterial Species ◽  
Bacillus Species ◽  
Erwinia Tracheiphila ◽  
Static Activity ◽  
Low Toxicity

Plant pathogenic bacteria in the genus Erwinia cause economically important diseases, including bacterial wilt of cucurbits caused by Erwinia tracheiphila. Conventional bactericides are insufficient to control this disease. Using high-throughput screening, 464 small molecules (SMs) with either cidal or static activity at 100 µM against a cucumber strain of E. tracheiphila were identified. Among them, 20 SMs (SM1 to SM20), composed of nine distinct chemical moiety structures, were cidal to multiple E. tracheiphila strains at 100 µM. These lead SMs had low toxicity to human cells and honey bees at 100 µM. No phytotoxicity was observed on melon plants at 100 µM, except when SM12 was either mixed with Silwet L-77 and foliar sprayed or when delivered through the roots. Lead SMs did not inhibit the growth of beneficial Pseudomonas and Enterobacter species but inhibited the growth of Bacillus species. Nineteen SMs were cidal to Xanthomonas cucurbitae and showed >50% growth inhibition against Pseudomonas syringae pv. lachrymans. In addition, 19 SMs were cidal or static against Erwinia amylovora in vitro. Five SMs demonstrated potential to suppress E. tracheiphila when foliar sprayed on melon plants at 2× the minimum bactericidal concentration. Thirteen SMs reduced Et load in melon plants when delivered via roots. Temperature and light did not affect the activity of SMs. In vitro cidal activity was observed after 3 to 10 h of exposure to these five SMs. Here, we report 19 SMs that provide chemical scaffolds for future development of bactericides against plant pathogenic bacterial species.

Favorable effects in vitro and in vivo of two clinical isolates of Pseudomonas aeruginosa on nutritionally deficient Staphylococcus aureus strains

1973 ◽  
Vol 19 (8) ◽  
pp. 973-981 ◽  
Author(s):  
T. Gadbois ◽  
J. De Repentigny ◽  
L. G. Mathieu
Keyword(s):  
Staphylococcus Aureus ◽  
Pseudomonas Aeruginosa ◽  
Peritoneal Cavity ◽  
Pathogenic Bacteria ◽  
Bacterial Species ◽  
Mixed Cultures ◽  
Rabbit Skin ◽  
Metabolic Activities

We have studied aspects of interbacterial ecology with nutritionally dependent Staphylococcus aureus strains; they were grown in association with Pseudomonas aeruginosa in systems of mixed cultures and infections in vitro in a semisynthetic medium and in vivo in mouse peritoneal cavity and rabbit skin. In mixed cultures and in P. aeruginosa culture filtrates, thymine and tryptophan deficiencies in staphylococci were partly overcome. This is probably because P. aeruginosa supplied the essential metabolites required to ensure growth; however, other metabolic activities could also be involved. Other experiments showed that the sensitivity of thymineless staphylococci to nucleoside inhibitions was alleviated. In mixed infections with P. aeruginosa, the S. aureus thymineless strain has shown a greater ability to survive in the peritoneal cavity of mice than when injected alone, even when one species was injected after the other with different doses of bacteria. The examination of the liquid from the peritoneal cavity of infected mice by fluorescence microscopy after fluorochroming with acridine orange or auramine O has revealed that Pseudomonas endotoxin seems to damage leucocytes and consequently reduces the phagocytosis of Staphylococcus cells.Necrosis in rabbit skin was mainly due to S. aureus when both species were injected together intradermally; the thymineless strain was less harmful than the parent strain.It seems that survival and even growth of nutritionally dependent strains of a bacterial species can be favored by the metabolic activities of another species in mixed cultures and infections, in this instance S. aureus by P. aeruginosa. This phenomenon among others could be a determinant of bacterial pathogenicity for nutritionally dependent pathogenic bacteria; thus associated organisms could determine the effective pathogenicity of nutritionally dependent bacteria by contributing essential nutrilites at the site where infection is initiated.

scholarly journals Blue and red light photoemitters as approach to inhibit Staphylococcus aureus and Pseudomonas aeruginosa growth

2022 ◽  
Vol 82 ◽  
Author(s):  
I. D. C. Galo ◽  
R. P. Prado ◽  
W. G. Dos Santos
Keyword(s):  
Staphylococcus Aureus ◽  
Pseudomonas Aeruginosa ◽  
Visible Light ◽  
Blue Light ◽  
Bacterial Infections ◽  
Pathogenic Bacteria ◽  
Bacterial Species ◽  
Red Light ◽  
High Rate

Abstract The ability of pathogenic bacteria acquire resistance to the existing antibiotics has long been considered a dangerous health risk threat. Currently, the use of visible light has been considered a new approach to treat bacterial infections as an alternative to antibiotics. Herein, we investigated the antimicrobial effect of two range of visible light, blue and red, on Staphylococcus aureus and Pseudomonas aeruginosa, two pathogenic bacterial commonly found in healthcare settings-acquired infections and responsible for high rate of morbidity and mortality. Bacterial cultures were exposed to blue or red light (470 nm and 660 nm) provided by light-emitting diodes - LED. The fluencies and irradiance used for blue and red light were 284.90 J/cm2, 13.19 mW/cm2 and 603.44 J/cm2, 27.93 mW/cm2 respectively. Different experimental approaches were used to determine the optimal conditions of light application. Only exposure to blue light for 6 hours was able to inhibit about 75% in vitro growth of both bacterial species after 24 hours. The surviving exposed bacteria formed colonies significantly smaller than controls, however, these bacteria were able to resume growth after 48 hours. Blue light was able to inhibit bacterial growth upon inoculation in both saline solution and BHI culture medium. We can conclude that blue light, but not red light, is capable of temporarily retarding the growth of gram negative and gram positive bacteria.

scholarly journals The Inhibition Potentials of Different Honey against Staphylococcus aureus, Escherichia coli and Bacillus species Isolated from Clinical Source

2020 ◽  
pp. 46-55
Author(s):  
Akani, Nedie Patience ◽  
Amadi Wemedo, Samuel ◽  
Njoku, Onyedikachi Egbuchulem
Keyword(s):  
Escherichia Coli ◽  
Staphylococcus Aureus ◽  
Bacillus Cereus ◽  
Pathogenic Bacteria ◽  
Inhibition Efficiency ◽  
Minimum Bactericidal Concentration ◽  
Bacterial Species ◽  
Diffusion Method ◽  
Bacillus Species ◽  
Clinical Source

As a result of the increased prevalence of antibiotic resistance among different bacteria, different plants and other natural products have been studied and found to be highly effective against pathogenic bacteria. Honey, over the years has been used as an antibacterial agent to treat certain infections caused by bacteria and is believed to be effective especially in rural areas. This study was thus aimed at comparing the effect of different honey samples against some pathogenic bacteria (Escherichia coli, Staphylococcus aureus and Bacillus cereus) isolated from clinical source. This study was carried out in the microbiology laboratory, department of microbiology Rivers State University Nigeria from January 2018 to August 2019. The antibacterial sensitivity test was carried out using agar well diffusion method while the Minimum inhibitory concentration and Minimum bactericidal concentration were determined using broth tube micro dilution technique in two fold dilution. The inhibition efficiency of the honey samples on the test organisms increased with increasing concentration from 20 to 100% as 100% concentration had the highest zone of inhibition. Staphylococcus aureus (6.33 mm – 26.33 mm) was the most sensitive to the honey samples while Bacillus cereus (0.00 – 19.67 mm) was less sensitive. At concentrations of 20 – 80%, raw and Rowse honey were more effective on E. coli compared to Princenic Global honey, while at 100%, Princenic Global honey was more effective on Staphylococcus aureus. Raw and Rowse honey were more effective at 20 -60% concentrations followed by Princenic Global honey; whereas at 80 -100% concentrations, Raw and Princenic Global honey were more effective. Bacillus cereus was resistancet to the honey samples at 20 – 60% but sensitive at 80 – 100% concentrations to Rowse, Raw and Princenic Global honey. The inhibition efficiency of the honey samples on the growth of the tested organisms was found to be dependent on the concentration and type of honey used, as well as they type of organism tested. The result of the minimum inhibitory and minimum bactericidal concentration showed that Staphylococcus aureus was inhibited most at a lower concentration of 25% compared to other bacteria isolates. All honey samples tested did not show any bactericidal effect but was bacteriostatic to some of the tested organisms. Pharmacological standardization and clinical evaluation on the effect of honey is essential before honey can be used as a preventive and curative measure to common diseases related to the tested bacterial species.

scholarly journals Synergistic antibacterial combination of Lavandula latifolia Medik. essential oil with camphor

2020 ◽  
Vol 0 (0) ◽  
Author(s):  
Nursenem Karaca ◽  
Görkem Şener ◽  
Betül Demirci ◽  
Fatih Demirci
Keyword(s):  
Staphylococcus Aureus ◽  
Essential Oil ◽  
Antibacterial Effect ◽  
Synergistic Effects ◽  
Pharmaceutical Formulations ◽  
Human Pathogens ◽  
Broth Microdilution ◽  
Antibacterial Effects ◽  
Lavandula Latifolia

AbstractCombination of various compounds and essential oils for pharmaceutical formulations withdraw attention. In this present study, it was aimed to evaluate the in vitro potential synergistic antibacterial effect of Lavandula latifolia (spike lavender) essential oil with camphor by using the checkerboard method against the human pathogens; Staphylococcus aureus and Listeria monocytogenes. Pharmacopoeia quality L. latifolia essential oil and racemic camphor were analyzed and verified by GC-FID and GC/MS, simultaneously. In vitro antibacterial activity of essential oil and camphor (MIC range: 0.16–20 mg/mL) and standard antimicrobial clarithromycin (MIC range: 0.125–16 μg/mL) were carried out by broth microdilution against S. aureus and L. monocytogenes standard strains, respectively. Resulting antibacterial effects were evaluated for their fractional inhibitory concentrations (FICs) as antagonistic, additive and synergistic effects. The analytical results showed that the major component of essential oil was linalool (45.2%) and 1,8-cineole (25.6%). Antibacterial effects of essential oil were determined as MIC 1.25–5 mg/mL. As a result of the experiments, L. latifolia essential oil–camphor combinations were identified as “synergistic (FIC ≤ 0.5), and additive (0.5 < FIC ≤ 1)” in the respective combinations, suggesting further evaluation for formulations for potential antimicrobial applications in food and pharmaceuticals.

scholarly journals Staphylococcus aureus Serves as an Iron Source for Pseudomonas aeruginosa during In Vivo Coculture

2005 ◽  
Vol 187 (2) ◽  
pp. 554-566 ◽  
Author(s):  
Lauren M. Mashburn ◽  
Amy M. Jett ◽  
Darrin R. Akins ◽  
Marvin Whiteley
Keyword(s):  
Staphylococcus Aureus ◽  
Pseudomonas Aeruginosa ◽  
Pathogenic Bacteria ◽  
Iron Acquisition ◽  
Low Oxygen ◽  
Dialysis Membrane ◽  
Opportunistic Human Pathogen ◽  
The Impact

ABSTRACT Pseudomonas aeruginosa is a gram-negative opportunistic human pathogen often infecting the lungs of individuals with the heritable disease cystic fibrosis and the peritoneum of individuals undergoing continuous ambulatory peritoneal dialysis. Often these infections are not caused by colonization with P. aeruginosa alone but instead by a consortium of pathogenic bacteria. Little is known about growth and persistence of P. aeruginosa in vivo, and less is known about the impact of coinfecting bacteria on P. aeruginosa pathogenesis and physiology. In this study, a rat dialysis membrane peritoneal model was used to evaluate the in vivo transcriptome of P. aeruginosa in monoculture and in coculture with Staphylococcus aureus. Monoculture results indicate that approximately 5% of all P. aeruginosa genes are differentially regulated during growth in vivo compared to in vitro controls. Included in this analysis are genes important for iron acquisition and growth in low-oxygen environments. The presence of S. aureus caused decreased transcription of P. aeruginosa iron-regulated genes during in vivo coculture, indicating that the presence of S. aureus increases usable iron for P. aeruginosa in this environment. We propose a model where P. aeruginosa lyses S. aureus and uses released iron for growth in low-iron environments.

scholarly journals Identification and antibiogram study of bacterial species isolated from milk samples of different locations in Bangladesh

2016 ◽  
Vol 1 (3) ◽  
pp. 457-462 ◽  
Author(s):  
Md Nuruzzaman Munsi ◽  
Nathu Ram Sarker ◽  
Razia Khatun ◽  
Mohammed Khorshed Alam
Keyword(s):  
Escherichia Coli ◽  
Staphylococcus Aureus ◽  
Pathogenic Bacteria ◽  
Bacterial Species ◽  
Salmonella Typhi ◽  
Diffusion Method ◽  
Biochemical Tests ◽  
Public Health Importance ◽  
Milk Samples ◽  
First Choice

Cow’s milk containing pathogenic bacteria is an important threat to the consumers. The objectives of the present study were to identify the bacterial agents of public health importance in milk samples (n=35) of different locations and to determine their sensitivity to different antibiotics. The milk samples were collected and transported aseptically and subsequently allowed for culture in bacteriological media, Gram’s staining and biochemical tests for the identification of bacterial species. The bacteria identified were Staphylococcus aureus, Escherichia coli and Salmonella typhi, and their prevalence, in case of vendor milk specimens (n=28), were 96.43%, 53.57% and 35.71% respectively, and of brand milk specimens (n=7), were 42.86 %, 28.57% and 0%, respectively. This suggests that cautionary measures should be taken for quality milk production and consumption. The antibiotic sensitivity test was done by disc diffusion method and the average inhibition zones, in case of Staphylococcus aureus, were 32 mm for oxytetracycline, 26 mm for amoxicillin, 35 mm for ciprofloxacin, 27 mm for cefotaxime, 30 mm for ceftriaxone, 30 mm for azithromycin, and 26 mm for erythromycin; in case of Escherichia coli, were 5 mm for oxytetracycline, 9 mm for amoxicillin, 22 mm for ciprofloxacin, 30 mm for cefotaxime, 31 mm for ceftriaxone, 15 mm for azithromycin, and 0 mm for erythromycin; in case of Salmonella typhi., were 25 mm for oxytetracycline, 24 mm for amoxicillin, 38 mm for ciprofloxacin, 31 mm for cefotaxime, 34 mm for ceftriaxone, 24 mm for azithromycin, and 0 mm for erythromycin. Therefore, ciprofloxacin and ceftriaxone may be the antibiotics of first choice, and cefotaxime and azithromycin may be the second choice among the test antibiotics for the treatment of illness caused by these bacteria.Asian J. Med. Biol. Res. December 2015, 1(3): 457-462

scholarly journals Hidden reservoirs of pathogens in dental settings

2021 ◽  
Vol 17 (1) ◽  
pp. 73-79
Author(s):  
Silpi Chatterjee ◽  
Keyword(s):  
Staphylococcus Aureus ◽  
Mobile Phones ◽  
Nosocomial Infections ◽  
Bacterial Species ◽  
Brain Heart Infusion ◽  
Bacillus Species ◽  
Coagulase Negative Staphylococcus ◽  
Cross Contamination ◽  
Sterile Saline ◽  
Predominant Species

Nosocomial infections are a major concern to both clinicians and health care seekers. Investigations have suggested that laptops & mobile phones may contribute to cross-contamination and can serve as vehicles for infection transmission. Therefore, it is of interest to document the data on hidden reservoirs such as mobile phones and laptops of pathogens in dental settings at the Hazaribag college of dental sciences and Hospital, Jharkhand. The samples were collected from 25 laptops and 25 mobile phones from dentists working in a dental college in Hazaribag city. The samples were collected aseptically using sterile cotton swabs dipped in sterile saline by rotating the swabs on the keyboard surfaces of laptops and mobile phones, inoculated into Brain Heart Infusion broth, vortexed for 1 minute in Fischer Vortex Genie 2 on highest setting & streaked immediately on 5% sheep blood agar plates and were incubated at 370C for 24 hours aerobically. The isolates were identified based on the colony morphology, colony characteristics and biochemical reactions. The bacterial species isolated were Staphylococcus aureus, Coagulase negative Staphylococcus, Bacillus species, Enterococci, Micrococci, and Pseudomonas etc. Predominant species isolated was Staphylococcus aureus and least was Micrococci. Higher percentage of organisms was found at the Department of Periodontics, Endodontics and least was found in Department of Public Health Dentistry. The percentage and type of organism isolated from keyboards of laptops and mobile phones were similar. Thus, laptops and mobile phones act as vehicles for transfer of potential pathogens associated with dental hospitals. Disinfecting the hands prior to examination of patients and disinfection of laptops and mobiles with alcohol wipes should be done to prevent nosocomial infections.

scholarly journals Whole-Genome Sequencing of Invasion-Resistant Cells Identifies Laminin α2 as a Host Factor for Bacterial Invasion

mBio ◽  
2017 ◽  
Vol 8 (1) ◽  
Author(s):  
Xander M. van Wijk ◽  
Simon Döhrmann ◽  
Björn M. Hallström ◽  
Shangzhong Li ◽  
Bjørn G. Voldborg ◽  
...  
Keyword(s):  
Staphylococcus Aureus ◽  
Endothelial Cells ◽  
Pathogenic Bacteria ◽  
Bacterial Invasion ◽  
Human Pathogens ◽  
Specific Domain ◽  
Cellular Invasion ◽  
Group A ◽  
Group B ◽  
Laminin Α2

ABSTRACT To understand the role of glycosaminoglycans in bacterial cellular invasion, xylosyltransferase-deficient mutants of Chinese hamster ovary (CHO) cells were created using clustered regularly interspaced short palindromic repeat (CRISPR) and CRISPR-associated gene 9 (CRISPR-cas9) gene targeting. When these mutants were compared to the pgsA745 cell line, a CHO xylosyltransferase mutant generated previously using chemical mutagenesis, an unexpected result was obtained. Bacterial invasion of pgsA745 cells by group B Streptococcus (GBS), group A Streptococcus, and Staphylococcus aureus was markedly reduced compared to the invasion of wild-type cells, but newly generated CRISPR-cas9 mutants were only resistant to GBS. Invasion of pgsA745 cells was not restored by transfection with xylosyltransferase, suggesting that an additional mutation conferring panresistance to multiple bacteria was present in pgsA745 cells. Whole-genome sequencing and transcriptome sequencing (RNA-Seq) uncovered a deletion in the gene encoding the laminin subunit α2 (Lama2) that eliminated much of domain L4a. Silencing of the long Lama2 isoform in wild-type cells strongly reduced bacterial invasion, whereas transfection with human LAMA2 cDNA significantly enhanced invasion in pgsA745 cells. The addition of exogenous laminin-α2β1γ1/laminin-α2β2γ1 strongly increased bacterial invasion in CHO cells, as well as in human alveolar basal epithelial and human brain microvascular endothelial cells. Thus, the L4a domain in laminin α2 is important for cellular invasion by a number of bacterial pathogens. IMPORTANCE Pathogenic bacteria penetrate host cellular barriers by attachment to extracellular matrix molecules, such as proteoglycans, laminins, and collagens, leading to invasion of epithelial and endothelial cells. Here, we show that cellular invasion by the human pathogens group B Streptococcus, group A Streptococcus, and Staphylococcus aureus depends on a specific domain of the laminin α2 subunit. This finding may provide new leads for the molecular pathogenesis of these bacteria and the development of novel antimicrobial drugs. IMPORTANCE Pathogenic bacteria penetrate host cellular barriers by attachment to extracellular matrix molecules, such as proteoglycans, laminins, and collagens, leading to invasion of epithelial and endothelial cells. Here, we show that cellular invasion by the human pathogens group B Streptococcus, group A Streptococcus, and Staphylococcus aureus depends on a specific domain of the laminin α2 subunit. This finding may provide new leads for the molecular pathogenesis of these bacteria and the development of novel antimicrobial drugs.

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