Antibiotics - Science topic

We want to determine MIC(minimum inhibitory concentration) for Meropenem and Imipenem by microdilution broth but I want to know if it is practical to use injectable antibiotics instead of antibiotics used for research in diagnostics test.

In fact, I didn't find a reference to provide guidance on this issue..

It would be a great kindness if you could help me!

I am experiencing contamination issues while working with a fungus I intend to use for infecting animals. I am considering adding antibiotics to the growth medium to address this. Has anyone tried this approach or have recommendations on its effectiveness and potential risks.

Hi everyone!

I was wondering what kind of infection this was? Also, have anyone tried expressing protein complex (eg: over 1MDa) with antibiotics? Did it affect the protein yield?

Thank you!

PZC

Nantural PH of mixed plant extract good for photocatalytic degradation of antibiotics

As we know that Actinomycetes produce most of the clinical used antibiotics, therefore, what mechanisms do they use to protect themselves from the antibiotics they made?

can i increase the antibiotics concentration in media preparation for cell culture when Culturing normal cell lines?

can i increase the antibiotics concentration in media preparation for cell culture when Culturing normal cell line?

Here I am using DMEM with 10% serum and 1% antibiotics.

Dear Research Community,I am exploring the potential of reformulating a new antibiotic by combining it with an extract from a plant. I would like to know if anyone has experience or insights regarding the feasibility of this approach. Specifically, I am interested in:

Your expertise and any resources you could share would be greatly appreciated!Thank you in advance for your assistance.

I want to extract plasmid DNA from clinical isolates of bacteria to detect multiple genes of ESBL as TEM, SHV, OXA and CTX_M, what are the suitable antibiotics add to bacterial media?

I was looking for the most recent antibiotic to be approved for clinical use that has a significantly different structure from previous antibiotics. Preferrably sourced from the natural environment. This would usually be referred to as "first in class".

Tea tree oil is a powerful natural antibiotic. Its antimicrobial properties make it great for cuts, wounds, and infections. Other oils like oregano and thyme also have strong antibacterial effects.

Visit here:- https://hbno.com/products/tea-tree

What are your opinions on it?

Hi,

My lab was doing experiment with a Escherichia strain. It seems it was working well, but after about just 1 month, the negative controls for transformation became positive to Kanamycin and Spectinomycin. I didn't check other antibiotics.

For spectinomycin if we put 2 times (120µg/ml) the amount of antibiotics, the colonies are fewer, but there are still there.

Is there an explanation for that?

Kanamycin stock was expired but spectinomycin stock is quite new.

And again it seemed like it was working about a month ago.

Tuberculosis (TB) is an infectious disease caused by the bacterium Mycobacterium tuberculosis, primarily affecting the lungs but capable of impacting other parts of the body. Once one of the world’s leading causes of death, TB rates significantly declined during the 20th century due to the introduction of effective antibiotics and improved public health measures. However, in recent years, there has been a concerning resurgence of TB, especially in developing regions and among vulnerable populations.

Hi all,

So I am continuously experiencing a very weird phenomenon (see images attached). I am trying to get E.coli DB3.1 cells competent together with SURE and XL-Blue cells. I always streak out the glycerol stocks of each on LB plates with relevant antibiotics, pick a colony for an overnight 5ml culture at 37C with the relevant antibiotics (tetracycline 15 ug/ml for XL-blue and SURE because I want to maintain the F-plasmid), and then inoculate overnight 1/100 in 120ml LB (10g peptone, 10g salt, 5 g yeast extract per 1 L media) in 200ml Erlenmeyer flasks. The cells grow fine to an OD of 0.3-0.35 in about 3 to 3.5 hours whereafter I put the flasks on ice for about 30 min to stop growth. When I spin them down (10 min at 3000 rpm), the pellet looks see-through/lysed and flaky and does not stay attached at all. The cells don't look like they are alive. Has anyone else experienced this? How could the cells be dead if the OD600 is increasing? I have been making competent cells for about 6 years and this has never happened to me. What am I doing wrong?

I used PCR to add a few nucleotides to the 3' end of a gene on a pc3.1 plasmid and produced a linear vector with 18bp overlap at 5' and 3'. Then I used DpnI to cut off the template chain, transformed the linearized vector into BL21, plated it, picked a single clone and continued to culture it in Kan-resistant LB culture medium, and then handed it over to a sequencing company. The sequencing company said that my bacteria did not grow when further expanded and could not be sequenced. So I extracted the plasmid and sent it for sequencing again, and it still showed no signal. I simply asked the sequencing company to continue testing the Kan resistance gene, and it still showed no signal. If it is because the antibiotics are degraded, then when I did the transformation, the negative control that did not transform any genes did not have any colonies, which shows that the antibiotics worked. I am very confused. If the plasmid was not successfully transformed, why can it grow in the resistance culture dish?

currently conducting a study on antibiotic resistance and using MIC assay to evaluate the effectiveness of colistin antibiotics and using standard broth microdilution assay but encountering inconsistent results. I used the following methods-

1. Concentration of antibiotics were 256µg/ml . The Ab is diluted in broth to create a series of 2 fold concentrations. Here is the result of MIC assay and we found inconsistent results after measuring ELISA machine.

Hello ! I seeded fibroblasts from ATCC PCS - 201 - 012. But they look round. They don't have an elongated shape And it's been 7 days.

I used medium DMEM with 10% FBS and antibiotics, Fibroblast Basal Medium

What could be wrong?

I am trying to establish a stable protein-producing cell line. Transfection and antibiotic selection was successful in suspension culture using the serum-free Expi expression medium. However single cells do not growth well on plates. I tried adding 5% FBS or using conditional medium, but it did not work.

Thank you very much if you can provide some tips or share your experience on ExpiCHO cell culture.

My challenge is that the solubility of the antibiotic Cefixime in water is low, making it difficult for me to prepare a solution, as it tends to precipitate. I would greatly appreciate your assistance and guidance on this matter. Thank you!

Hi Everyone

First year PhD student in London here, I'm new to Caco-2 cells.

I have two issues that are bugging me. Does anyone have any advice on how I can navigate these problems?

The first one, as shown in the first image, where cells seem to clump together in a wall like structure, and there are cells growing on one side but none on the other side of this 'wall'. This is super annoying because I seed the cells and let them grow for a week, only to find that the cells on one side of the plate have died or disappeared so I essentially waste a week and media.

The second one, are the black rod like structures bacteria? I'm treating my cells with media in the absence of antibiotics for a gentamicin protection assay for 24 hours but normally, I do use pen-strep 1%. Cell viability in the potentially infected regions appears to be severely limited. However, the media is not cloudy?!

Thanks so much!

Pranaya

Can someone explain to me how was the MIC of MO in combination and MIC of antibiotic in combination was calculated? as shown in the attached file below.

I am doing a gene editing experiment and I want to edit two sites at the same time, so there are two resistance genes, can I add two antibiotics to the cell after transfection 72 hours or do I add one antibiotic to the cell first and then add the other antibiotic to the screen? Is it possible that screening after two weeks of transfection has no effect?

I am on gene work to express gene of interest in some Bacillus species. Thus far, i need to try some RBS in Vector which is optimized for bacillus subtilis.

Before i design vector to express in other species , I have transformed subtilis vector in other species and then i could select transformants by antibiotic selection

I have known GoI cannot be expressed without RBS and I have to insert RBS depends on bacteria strain individually.

so i wondered if there's no working RBS then Resistant gene in vector also cannot work???

Thank you in advance!!

Hi everyone,

I started to use SKBR3 breast cancer cell line in some of my experiments, but, I'm having some porblems to culture them properly. Currently, I'm using DMEM/F12 medium + 10% FBS + antibiotics. According to ATCC, they recommend the use of McCoy 5a medium. Is it extremely neccesary to use that medium? Do you people have experience with some other medium instead of McCoy?

Thank you very much for your replies and advices

I'm going to transfect cells with expression plasmids and later siRNAs against the same gene. Is it true that penicillin/streptomycin in the media negatively affects these processes? Shout I use media without antibiotic even when I'm seeding the cells?

Thank you for your help in advance!

I use the psip-403 vector that contains the erythromycin resistance gene for cloning, and I also tested several strains of Escherichia coli bacteria (top10f, dh5 alpha) for this purpose, and the cloning results were that both cloning DH5-a harboring erythromycin resistance gene and non-cloning DH5-a survive in erythromycin contained agar plate. Im sure that the cloning was successful and I tested and cultured different concentrations of the antibiotic erythromycin in the agar medium (1-0.2 g of antibiotic in 1 ml of ethanol for 50 ml culture medium). Also, I tested two different brands of antibiotics (molecule, sigma and pharmacy antibiotic tablet form) and used different solvents such as ethanol and dmso, but the results were still the same. If possible, please guide me in this matter.

Authors are invited to contribute under the scope that is defined as “Phage therapeutics and its implications in controlling the infectious diseases”. The submissions should clearly demonstrate the potentials/ or challenges of phage modalities via, original research (Phage Drug Development, Experimental Studies, Pharmacodynamic and Pharmacokinetic Studies, Preclinical, Clinical trials, Pilot studies, etc.), reviews, perspectives, technical reports and case studies particularly focusing on the application of phages in therapeutics. We propose the following vital themes:

You can access the Project's Public Page as below: https://www.frontiersin.org/research-topics/63638/emerging-trends-in-phage-therapeutics-to-overcome-antibiotic-resistance

If you need any assistance, then please forward you query.

Hello, I recently started working with antibiotics and I do not have that much experience of making dilutions accurately. I want to ask if I suppose to add 200mg of antibiotic in 100ml of water so what is the concentration of this stock solution in microgram?

Hi all,

I am wondering if anyone has any experience with using InvivoGen's Primocin antibiotic solution beyond the indicated expiry date when properly aliquoted and stored at -20degC. We have a relatively old stock in the lab (more than 1 year past the expiry date) and wondered if they are still effective to supplement culture media for maintaining primary human cells.

Alternatively, could anyone suggest simple tests to help determine the effectiveness of the antimicrobial activity of our 'expired' antibiotic solution?

Many thanks for your help and suggestions, Randy

I need a bacteriolytic antibiotic for destroy only extracelullar gram negative bacteria

Any suggestions?

How do antimicrobial stewardship programs balance the need for effective antibiotic therapy with concerns about overuse and antimicrobial resistance?

What strategies can be employed to address antimicrobial resistance and promote responsible antibiotic prescribing?

How can healthcare organizations measure the effectiveness of their antimicrobial stewardship efforts?

Hi,

This is actually just a general question out of curiosity. I have tried transfection using PEI both in suspension and attached cells, with and without antibiotic before and I don't see any difference. I understand that in lipid-based transfection, antibiotic can hinder the complex formation of lipid and DNA, but because PEI works differently I don't see why it is still advisable to use antibiotic-free media?

In our lab but we even don't change media in culture vessel for lipofectamine transfection and it still work perfectly, as long as we perform the DNA-lipofectamine complex formation in OPTIMEM first. It is also easier because we don't need to wash or change media prior to transfection.

Any other opinion?

i am doing THP-1 suspension culture and using cefotaxim as a antibiotic but after 4 passag my cell count was decline, so is it becuase cefotaxim my cell is decline

Hello researchers,

For now, I have developed PCR-confirmed and antibiotic-selected stable transgenic rice plants. I was doing qPCR expression analysis for my gene of interest, but I am getting no expression in my GOI. The selection marker is showing expression in the main experiment. During the trial, GOI expression and the antibiotic selection gene were present. We thought primers might have degraded, and we brought new primers even though it's not showing expression. What might be the reason? Have you come across any such problem? Please help me with this.

Thank you

Supriya

I need clarification on the appropriate timing for administering prophylactic antibiotics to cancer patients.

nanoparticles

Antimicrobial resistance (AMR) is a growing concern globally, particularly in third-world countries like the Philippines, where access to healthcare resources may be limited and antimicrobial stewardship practices may be lacking. Understanding the regional antibiograms, which outline the susceptibility of pathogens to specific antibiotics, is crucial for effective treatment strategies. However, there is a lack of comprehensive data on regional antibiograms in the Philippines, hindering the development of targeted antimicrobial therapies.

I am a student conducting research for my course and I am having trouble in finding a pill for Ketoconazole. However, there are a lot of creams available in the pharmacies. Would it be possible to use that cream when testing against grown fungi on plates?

This question addresses the practical implementation and impact of regional antibiograms, vital for tailoring antibiotic treatment and combating antibiotic resistance within diverse healthcare settings.

the concept is derived from Sundareshan & Khardori (2019) regarding the usage of antibiogram as Public Health Tools to Slow Down Antibiotic Resistance. it is indicated in the article that using antibiogram helps in detecting infectous substances that helps to determine the antibiotic needed in diagnosing a patient. what are the factors that should be considered in determining an infectious diseases to come up with the proper antibiotic need for diagnosis?

due to different patients being resistant to usual medications being prescribed to others, how can antibiogram be of help in determining the perfect antibiotic to be prescribed to the patient because antibiotics varies in treatment and dosage.

It is known that self-medication with antibiotics is an arising problem, becoming a major constituent to antibiotic resistance. Moreover, self-medication heightens the possibility of developing drug resistant infections. According to WHO, this is a prevalent problem in Southeast Asia, such as in the Philippines. With this in mind, it would be highly appreciated to receive answers to the query above, as to expound the knowledge regarding the various factors that cause antibiotic diversion.

An important factor to consider when providing antibiotics is the possibility of the bacteria gaining resistance to it. My questions pertains to how these bacteria are able to gain resistance and the mechanisms involved for it to happen? And what can we possibly do to lessen the chances of this happening?

Good morning Research Gate scientists

I have an LB agar plate for DH5a bacteria cell storage at 4C for 6 weeks, and I tried to subculture to a new plate plenty of times but I could not get colonies at all. the colony on the storged plate is not white, as usual, It is a light yellow color.

Then, I tried to subculture using a glycerol stock, I used a loop dipped deeply on the stock, and one loop streaked on the agar plate but still, no colony appeared on the agar surface, though I tried to avoid thaw-freezing for the stock.

No antibiotic was added to the plates because it was just a simple bacteria subculture. And plates were warmed and dried before subculture and the plates were incubated at 37 C overnight, I don't know the problems. Thanks in advance for your assist

Providers should make an effort to understand local resistance patterns including those of the referring hospitals. Such data are relevant to monitor longitudinal resistance trends and formulate regional public health interventions. The institutional antibiograms often contained insufficient isolates and multidrug resistant isolates were not routinely tested.

i have recently done a disk diffusion assay where by i measure the zone of inhibition of 5 antibiotics on 7 different pathogens, i want to establish if there is any significant difference between the zones of inhibition acquired by each antibiotics to the pathogens overall. as it is a large data set i am confused as to what the appropriate statistical test would be, i have attached the excel file of my data and also my prism file. Any advice welcome , thank you!

Hi anyone who reads this, I am a MRes student looking at antibiotic application on S. aureus biofilms. After disrupting my biofilm to quantify antibiotic application on TSA. I re exposed the same disrupted bacteria to TSB on a 96 well plate. The TSA plate quantified growth, whilst the TSB plate showed a lack of growth at some antibiotic concentrations that had grown on TSA. When re exposing the plated bacteria back to TSA there was a lack of growth.

I am currently engaged in research pertaining to multidrug-resistant bacteria, including but not limited to Staphylococcus aureus, Klebsiella pneumonia, Pseudomonas aeruginosa, Enterococcus faecalis, Escherichia coli, and Bacillus cereus. My objective is to identify the three least efficacious antibiotics against these strains and, more broadly, to ascertain their general resistance patterns.

Does anyone have good lab practices or experience of growing primary cells without antibiotics and anti-fungal?

Recently I ordered primary airway epithelial cells (adherent) from ATCC. They provided Anti-anti (penicillin + amphotericin B solution) along with basal media. so I prepared media with anti-anti solution and re suspend cells. so I observed cells were not attaching for 2 days and 3rd day there was contamination without change of media color. it was rod shaped bacteria with cells when i saw under microscope.

So when I complaint to ATCC, they suggested me some points. One of them was not to use anti-anti solution (antibiotics), as it can cause stress to primary cells.

Now I am planning to grow primary cells without adding antibiotics, But I am scared that there will be contamination and I dont want to lose cells (I have only single vial).

Any suggestions?

I have tried to read about this but I don't find definitive answers.

I am trying to lentivirally transduce a mouse cell line with a few different plasmids (each encoding a different antibiotic resistance gene, namely puromycin, hygromycin and G418). After successfully transducing the cells a first time (with the puromycin resistance-containing plasmid), it now looks like when I transduce the cells with the hygromycin resistance-containing plasmid they don't die at the hygromycin concentration established during the antibiotic titration.

Has anyone experienced this?

I found this paper, but it doesn't seem to answer my question fully: https://www.sciencedirect.com/science/article/abs/pii/S0003269709008434

Any six antibiotics of each

Hi All,

My question is clear, so why other antibiotics and antifugal could be used, why chloramphenicol and Cycloheximide exactly?

I don't want routine answers, isolating, inhibiting, no pathogenic bacteria and fungi ...etc

Thanks

This question was asked to inquire into how incorporating regional antibiograms, which document local microbial resistance patterns, into diagnostic microbiology practices can help combat antibiotic resistance by guiding the selection of appropriate antibiotic therapies tailored to the specific resistance profiles in a given region. In addition, how do the overuse, misuse, and abuse of antibiotics contribute to the ongoing challenge of antibiotic resistance, and what strategies can be implemented to promote prudent antibiotic use for public health?

We have done a dose response study for a synthetic antibiotics. We have noticed that bacterial growth inhibition decreases as the concentration of the decrease and show a zero inhibition at 0.015 uM. But, then at lower concentration (0.0078 and .0039 uM) the inhibition retrieved and was 10 and 22 percentage respectively. This is a results for three trials. How can we explain this phenomenon?

Hello.

I am trying to culture Agrobacterium GV 3103 and EHA105 in 15 mL LB media with the antibiotics kanamycin and rifampicin (100 ug/mL & 20 ug/mL)(added 200 uL of previously normally cultured Bacterial solution) . But, for some reason, after 12 hours of agitation (200 rpm), some bacteria don't develop. When I repeat the experiments, sometimes one specific sample grows normally and the other does not. So far, I haven't seen any consistency in my attempts, for example, I have alfa and beta, one day alfa develops normally while beta doesn't , but the very next day only beta does and alfa is not developed. I suspected that it was because of the 50 mL plastic tube, so I changed to Erlenmeyer flask, but the trouble persists. Even in some samples, I centrifuged the LB to pellet and check if any bacteria was therein, but sometimes I have got not any pellet. I suspect this problem is probably a basic laboratory trouble. Still, I would appreciate any suggestion that can help me to find out how to get a consistent growth of my bacterial. Thank you. (PD: The bacteria I am trying to cultivate was previously isolated from solid LB (with antibiotics) and was chosen after PCR verification).

Dear Researchers

Are DAPI and PI staining are suitable for bacterial live/dead imaging and counting after treatment with various concentration of antibiotics?

can you help me about this matter?

if we conjugate the antibiotics with Micro RNA, (the amount of added Micro RNA are equal in each samples) these caused to changes or final results.

Thanks for your valuable contributions

Hi all,

I've never worked with E.coli strains that already carry a plasmid and tried to make competent cells from them.. is it simply the usual protocol for chemically competent cells, but add the appropriate antibiotic in each step?

Your advice will be much appreciated

Cheers

Lisa

as I am working first time on antibiotics for analysis of MIC by broth dilution method.

I firstly prepared stock soln of 100mg/ml of ampicillin.

now I want to ask how much ampicillin from its stock solution I should transfer to 100microliter of LB medium in 96 microtiter plate ?

I have to detect & quantify the antibiotic residues from waterbodies but HPLC/LCMS is not available to me right now. Thus I am now thinking about the UV-NIR methods to detect & quantify the antibiotic residues from wastewater as an alternative. Is it enough? What do you think about it?

If you are an expert in this particular field please rise your voice, thanks a lot to all of you in advance.

I did lawn on an E. coli strain onto a plate of Mueller-Hinton agar. For other plates I got clear zones of inhibition, but for few particular antibiotics (CRO, OFX and CIP) against this strain some colony growth is observed. So is this strain resistant against these antibiotics?

Is there a benefit to the Caco2 cell intestinal model from antibiotics? I was trained cell culture in the late 90's at HyClone Laboratories. We never used antibiotics. But is seems everyone does now.

Hi,

In the last 3 months we are struggling with recurrent contaminations in our cell cultures. PCR results showed that the bacteria are Sphingopyxis sp. FD7 (by sequence alignment). Although I used several antibiotics that worked nicely as cocktail (Gentamycin+Nanomycopulitine+PSN), the bacteria usually are coming back a few days after I stop antibiotics. I treat the cells usually 2-4 weeks.

Does anybody know where can I look for data of antibiotics sensitivity? Or what is a possible source for this contamination (human? water bath? other?)?

I would appreciate any information that might help to get rid of this contamination.

Thanks in advance,

Orit

Hello,

I have been exposing human chondrocytes to LPS (Lipopolysaccharides from E. coli O111:B4) in concentrations from 1 µg/ml to 40 µg/ml for 24 h and 48 h and haven’t seen any decrease in cell viability assessed by MTT. Interestingly, results showed concentration-dependent increase in viability up to 150 %. After consultation with my colleagues, I cultivated cells in medium without antibiotics (previously, I used medium with ATB) but no decrease was observed either.

Do you have any idea why treatment with LPS does not cause cytotoxicity?

I’m trying to make a solution of metronidazole to add to drinking water of mice. I’m making a 100mg/mL solution but it won’t dilute. I need to filter sterilize the solution through a 0.2uM filter. I would love it if I can make it to 300mg/mL.

any suggestions?

some yellow, orange and white microbes were seen on some of the media. I'm not too sure about the type of microbe whether bacteria or fungi. I would like to know whether I can add antibiotics to repress their growth and ways to apply it

Lots of studies in adults and children, mainly done in HICs, are advocating antibiotics only (conservative) management of acute non-perforated appendicitis. In LMICs, with poor access to healthcare, most patients present with perforation. Is there a role of conservative management of acute non-perforated appendicitis in children in LMICs?

I plated HepG2 into a 96-well plate using EMEM containing 10% FBS and 0.1% antibiotic. After 24 hours, when treating with doxorubicin, should I use media that has 10% FBS or FBS free media? Also, when running cell viability assay, can I still use the media with phenol red in it or do I need to switch to phenol red free media?

In my clinical observations, I absolutely think that extraction of teeth during pelvic infection can cause an existing pelvic infection to be excecerbated. That's why suitable antibiotic coverage (antibiotic prophlaxies) can be required before tooth extraction if the patient has a pelvic infection. I think this issue must be sufficiently researched, according to my clinical observations.

I have a query about carabcillin antibiotics is good option to put it in ypd agar for growing yeast or is it possible to grow them without antibiotic?

Kindly explain