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Article Title: Microbial biogeography of wine grapes is conditioned by cultivar, vintage, and climate

Date: September 16, 2013

Author: Nicholas Bokulich, John Thorngate, Paul Richardson, David Mills

Source: Proceedings of the National Academy of Sciences of the USA

Link: https://www.pnas.org/content/111/1/E139.full

Summary: This was a study done on wine! The researchers collected 235 samples of grape must (the crushed de-stemmed berries right before fermentation) from 8 different wineries in 4 California wine regions. They took DNA samples from all these grapes and sequenced specific genetic markers for bacteria and fungi instead of the entire genome. They found that a lot of factors make microbial differences, especially the region (geographic location) the grape was harvested from. The relative humidity and total precipitation of each area influences the specific niche for bacteria and fungi. The microbes found in a Cabernet Sauvignon from the Napa/Sonoma valley are completely different from grapes harvested from the central coast microbes. One example given was Zinfandel, which grape has thin skins leading to more berry breakage, these grapes carry more Gluconbacter and Lactobacillales which are commonly found on damaged fruits. This in turn, of course, leads to different flavors. For example, Oenococcus oeni carries out malolactic fermentation which adds a buttery flavor and reduces the acidity of the wine (think, Chardonnay) and Brettanomyces which adds a bit of a bitter bite and can sometimes spoil the wine (corked).

Connection: The authors talk about how microbes can be transferred in a modular way, by horizontal gene transfer, which we have covered in class. They go into detail about genome sequencing and online databases to help decipher sequences that are in the millions. They also briefly touch on fermentation.

Critical Analysis: I love wine, so this article was very appealing to me. I know the basic process of how wine is fermented and I know about different grapes and regions, but I never really thought about the microbes in different areas and in different wines and how they can affect them. I thought this study was really interesting in how environmental factors influence microbial populations and how it may be possible to predict how it can change with global climate change. Growers in the vineyards may be able to make changes to those conditions each year after tastings to be rid of anything that is undesirable or enhance things that are positive. I knew winemaking was an art in itself, but I’m fascinated to see how much science actually plays a part in the sometimes pretentious lifestyle.

Question: Will there ever be a wine that doesn’t cause a hangover!? 🙂 Just kidding. I’m wondering about the microbes in the soil and how they affect vine growth. There are microbes in the grapes themselves, but do the microbes in the soil play a part in taste at all? Or does that specifically reside on the personal palate of each individual person.

Article Title: Microbiological Contamination of Drugs during Their Administration for Anesthesia in the Operating Room

Date: April 2016

Author: Derryn A. Gargiulo, M.Pharm.Clin., Reg.Pharm.N.Z.; Simon J. Mitchell, Ph.D., F.A.N.Z.C.A.; Janie Sheridan, Ph.D., Reg.Pharm.N.Z., F.R.Pharm.S.; Timothy G. Short, M.B.Ch.B., M.D., F.A.N.Z.C.A.; Simon Swift, Ph.D.; Jane Torrie, M.B.Ch.B., F.A.N.Z.C.A.; Craig S. Webster, Ph.D.; Alan F. Merry, M.B.Ch.B., F.F.P.M.A.N.Z.C.A., F.R.C.A., F.A.N.Z.C.A.

Source: American Society of Anesthesiologists

Link: https://anesthesiology.pubs.asahq.org/article.aspx?articleid=2491392&resultClick=3

Summary: This article talks about the frequent lapses in aseptic techniques used in the operating room today, particularly with tools administering drugs to patients. Especially in large, busy hospitals were preoperative environments can get quite hectic, the aseptic techniques can often be overlooked during the sense of urgency to keep the patient on track for their scheduled surgery. This is in contrast with a normal, slower paced clinic setting where the anesthesiologist has ample time to set up equipment and utilize aseptic techniques as well as enough time between patients. The study was done in a major teaching hospital in New Zealand. They were able to obtain pathogenic microbes from 6.3% out of 300 general anesthesia procedures.

Connection: They talk a lot about how they swabbed the syringes and what they did to obtain their samples as well as what they did with them afterwards. They used multiple types of agar plates, included horses blood plates to culture different bacteria. They utilized the quadrant streaks, Gram-stains, and incubation. These are all things that we have done in lab.

Critical Analysis: I found this article very interesting. When we think of post-operative infections we rarely think that the anesthesiologist would play a part in that because they just administer the drugs to keep us asleep. They don’t exactly put their hands inside the patient like the surgeon does.

Question: What steps could be taken in order to ensure that all surgical equipment is suitable for surgery? There is an entire position devoted to sterilizing surgical equipment, but something seems to always slip through the cracks. Most syringes and needles are put into sterile packaging, I wonder if there is something that could be put in the paper of those packages that could potentially kill anything that was not cleared off during sterilization