Bacteria to the Rescue

Bacteria to the Rescue

By: Laura Murillo

Over the course of time, society has become more and more dependent on oil as the main source of energy. With increasing demand, most of the oil has to be brought from overseas. The ocean is very unpredictable, and despite taking all the precautions possible, oil spills are bound to happen. Together, scientists and engineers have developed different techniques to attempt removing oil from the surface of the oceans. One of these approaches consists of encircling oil batches so that they become thick enough to allow a skimmer or vacuum to collect. Most of the methods like the one mentioned require a lot of man-power, money and time. That is one of the reasons Cheng and his team focused on oil-degrading bacteria, Brevibacillus parabrev. By coating the bacteria in a shell of magnetic Fe₃O₄ nanoparticles (M-bacteria), they were able to encapsulate and isolate oil from water. The oil can then be removed by an external magnetic field, or it can be degraded by the same M-bacteria. One of the advantages of this approach is being able to recycle the magnetic nanoparticles, and the low cost of the bacterial cell fabrication. The possibilities are endless for this eco-friendly clean-up crew.

Figure 1. Graphical representation of M-bacteria encapsulating oil in water, then being separated by an outside magnetic field. Because of the bacteria's properties, the separated oil can be further broken down.

Original article:

Cheng, H., Li, Z., Li, Y., Shi, Z., Bao, M., Han, C., & Wang, Z. (2019). Multi-functional magnetic bacteria as efficient and economical Pickering emulsifiers for encapsulation and removal of oil from water. Journal of Colloid and Interface Science.

The Traveling Life within Fog

By Diana Cazares

Figure shows how similar the bacteria from each fog sample location is to the samples taken from the nearest ocean. Figure taken from Evans et al. 2019.

Walking through fog may feel like walking through a cloud. Clouds house bacteria way up in the sky, what would be found in the fog down on land? Aerosols are microbes and other particles found in the air. Aeromicrobiology is an

emerging science so the study of fogs is relatively new and unexplored.  The bacteria found in fog are the type thatcan reside in air, soil, and water. Fungal samples were taken in only the Namib desert.  In the Namib desert 545 bacterial OTUs total were found when Evans and her colleges took fog samples 4 different times.  From the coast of Maine, 8 different fog samples totaled 474 bacterial OTUs. Samples taken from the fog were similar to thosetaken from the ocean and rain water.  The difference in aerosols found in fog compared to aerosols found in clear air, isthey are richer and more abundant. Fog creates a favorable environment to source large amounts of microbes that make an impact on the environment.  Positive ways fog influences the environment is by increasing microbial and nutrient diversity in soils even in the driest of desserts.  Fog may also carry pollutants and pathogens that affects animals and plants.



Original Article:
Evans S, Dueker, Logan J., Weathers K. (2019). The biology of fog: results from coastal Maine and Namib Desert reveal common drivers of fog microbial composition. Science of the Total Environment. 647: 1547-1556.

How Grazing affects Soil Microbial Communities

By: Eliza Elizondo

The influence of grazing on soil microbial communities. The arrows represent the relationship between grazing, microbial communities, and land degradation. The plus signs represent the positive effects and the minus sings represent the negative effects in each relationship. Photo taken from Yang et al, 2018. 

Grazing is a practice used to promote plant diversity and preserve the ecosystem. Moreover, grazing can affect the soil microbial community by animal trampling and manure deposition. In a study conducted by Fei Yang and colleagues, at the Alpine Meadow and Wetland Ecosystem Research Station of Lanzhou University in China, three grazing systems were used. They were no grazing, winter grazing, and annual grazing. No grazing took place in a small area of 0.35 ha and no activity was done. Winter grazing took place in an area of 12 hectare with 12 yaks per hectare and was only grazed from October to April. Annual grazing took place in an area of 16 hectare with 18 yaks per hectare and was done in time intervals in order to allow plant regrowth. This study was performed in a period of five years and then soil samples were taken from 5 cm above the surface and up to 30 cm below the surface. Winter grazing was discovered to affect microbial communities by resource availability such as a decrease in total soil carbon and nitrogen. There was also an increase of fungi and a decrease of bacteria, an instability caused by the deposits of urine and manure. It was then determined that annual grazing was a more beneficial grazing system for microbial communities as it did not interfere with resource availability or microbe stabilization. 

Original Article:
Yang, F., Niu, K., Collins, C. G., Yan, X., Ji, Y., Ling, N.,... Hu, S. (2018). Grazing practices affect the soil microbial community composition in a Tibetan alpine meadow. Land Degradation & Development, 30(1), 49-59.

Microbial Competition in Aquatic Environment

By: Marco V. Munoz

Fig.1 Comparison between a fixed environment and control cultures (a) Sample of incubated microbes with additional iron granules used as electron donor. (b) Sample of incubated microbes in a control solution (no additional iron). (c) Sample of methane production after environment became sediment-free and iron was replaced by acetate solution.

One key element to preserve diversity in microorganisms of aquatic environments is by the interactions between species that benefit one or both organisms. Previous studies have proposed that acetate produced by acetogens can feed commensal acetoclastic methanogens. However, a recent study carried out by Palacios and colleagues demonstrated that corrosive microbial communities (MIC) such as methanogens and acetogens found in low-sulfide environments in the sea, compete with each other rather than cooperate under the presence of electrons from metals such as iron (Fe0). The researchers collected sediment cores samples from Bothnian Bay, Baltic Sea at a water depth of 15 m. All cultures made from collected samples were tested and examined over a time frame. The analysis identified Sporomusa and Methanosarcina dominated the corrosive microbial communities found in samples based on taxonomy and the number of microbes observed. Microbial cultures with the addition of iron granules demonstrated a much higher production of methane and acetate compared to control cultures and decreased in number of Sporomusa was based on methane production being higher than acetate; Also, acetoclastic methanogens were observed being inactivated after the environment became sediment-free and iron was substituted by acetate solution (Figure 1). This concluded independency and competition for electrons between these two species existing in the same habitat. This is important to understand because microbial induced corrosion accounts for 20% damage to industries which affects the economy and also contributes to water contamination that leads to health and environment issues affecting other living organisms.

Original Article

Palacios PA, Snoeyenbos-West O, Löscher CR, Thamdrup B, and Rotaru AE. (2019). Baltic Sea Methanogens Compete with Acetogens for Electrons from Metallic Iron. The Isme Journal. doi:10.1038/s41396-019-0490-0.

Microbes Take Flight.

Airplanes are the safest way to travel for both people and microbes. Air travel can serve as a conduit for infectious disease spread, these infections include influenza, measles, norovirus, cholera, shigellosis, and tuberculosis.  The way that the bacterial communities are derived from is by the human skin, oral commensals, and the environment. A very important factor in disease transmission is the movements of crew and passengers. During a recent research study to see what kind microbiomes could be found within an air cabin, it was identified that there was no meaningful difference between air and touch surface microbial diversity measures, the systematic patterns stayed the same for pre and post flights. Air cabin OTU signatures for air microbiome were there, but there were not that much for individual touch surface type microbiomes. The indicated reason behind the difference in microbiomes is that each flight start and end with a different surface cleaning routines. The vast majority of airplane microbes are human commensals or non-pathogenic and luckily it was proven to be true. Microbes are already very intimidating having them travel around the world can be freighting just imagine one of them being extremely pathogenic on a flight. Remember Ebola?

 Air and touch surface microbial diversity measures and systematic patterns. 

Original Article: 

Weiss, H., Hertzberg, V.S., Dupont, C. et al. Microb Ecol (2019) 77: 87. https://doi-org.tamiu.idm.oclc.org/10.1007/s00248-018-1191-3

Kiwi, Lock and Loaded

Author: Amanda Ponce

     Kiwellin is a protein isolate from kiwi (Actinidia chinensis) fruit and can also be found in most plant species. Zea Mays or maize carries a kiwellin protein that is versatile in defense mechanisms against fungal diseases. Maize is a domesticated crop that originated in the Americas that is distributed for food, feed livestock, used for biofuel, and is used as raw material. (Augistyn, A., Bauer, P., Duignan, B., Eldridge, A., Gregersen, E., McKenna, A., et al.) This article is centralized on Maize smut disease caused by the biotrophic fungus Ustilago maydis. There is an interaction between the fungal hyphae and an intruding cavity into the plant plasma membrane. Here, U. maydis secretes its effector proteins causing induced tumors. Cmu1 is a deregulated metabolic enzyme that is highly expressed during colonization of the plant and through biotrophic development. It is the conversion of chorismate to prephenate. Cmu1 is translocated to the cytosol, fluid in the plant membrane, and prevents the biosynthesis of salicylic acid that would mediate in plant immune responses against pathogens. Cmu1 has a crystal structure, and like the model organism Aro7p of Saccharomyces cerevisiae,  the both form a homodimer. A homodimer are two monomers that each have 9 α-helices and identical active sites. (Han, X., Altegoer, F., Steinchen, W., Binnebesel, L., Schuhmacher, J., Glatter, T., Giammarinaro, Pietro, I. et al 2019) Cmu1 is highly differentiated to Aro7p and other housekeeping enzymes in a region for allosteric regulation. This is activated and repressed by tryptophan and tyrosine because they biosynthesize proteins. In Aro7-, the binding site is made by the housekeeping genes, the α2 helix, and the adjacent loop for the amino acids tryptophan and tyrosine. Cmu1 however, has an addition α helix and an extensive loop region (ELR) that follow α2 helix and wrap around the structure. Basically, there is an absence of allosteric regulation by tryptophan and tyrosine in Cmu1.

Figure 1 shows a decrease in chorismate mutase activity of Cmu1 but not of Aro7p was led by an increase of concentration in ZmKWL1. Chorismate mutase was at 100% in the absence of ZmKWL1.

(Han, X., Altegoer, F., Steinchen, W., Binnebesel, L., Schuhmacher, J., Glatter, T., Giammarinaro, Pietro, I. et al 2019)

    

     What is interesting about the kiwellin protein is its versatile defense because of substrate binding block by altered ELR , the disabling of Cmu1 transport to the cytosol, and prohibiting the secretion of Cmu1. It is a paralogue gene meaning a derivative gene. Ultimately, there are more kiwellin proteins encoded that share the β barrel domain and disulfide bridge, permitting to target other fungal effectors.  This would not be eminently possible without model genetics. The models used in this investigation were to clone or model similar homodimer such Aro7p, the amino sequence in the hypothetical amino sequence of ZmKWL1, and genetic tagging used in the pull-down assays. Lastly, this article subjects the importance of environmental microbiology due to agricultural health hazards. A kiwellin protein variant can possibly be used to target other plant pathogens for safer and healthier uses.

Augistyn, A., Bauer, P., Duignan, B., Eldridge, A., Gregersen, E., McKenna, A., Petruzzello, M., Rafferty, J. P., Ray, M., Rogers, K., Tikkanen, A., Wallenfeldt, J., Zeidan, A., Zelazco, A., (2019 January 25) Corn. In Encyclopedia Britannica. Retrieved Octerber 23, 2019, from  https://www.britannica.com/plant/corn-plant.

Han, X., Altegoer, F., Steinchen, W., Binnebesel, L., Schuhmacher, J., Glatter, T., Giammarinaro, Pietro, I., Djamei, A., Rensing, S., Reissmann, S.,  Kahmann, R., Bange, G. A kiwellin disarms the metabolic activity of a secreted fungal virulence factor. Nature 2019; e-pub ahead of print 16 January 2019, doi: 10.1038/s41586-018-0857-9

Roaches and Bacteria! A match made in Heaven!

Periplaneta americana better known as the American cockroach is a pest found around the world. Most people dislike them and cringe at the mere sight of them. Well maybe except that one Japanese man (Yuta) who dated a cockroach (Lisa) for a year. That is a rare case though and most people don't like roaches much less date them. If anything they are uninvited guests in homes, hotels, restaurants and even hospitals. They are a nuisance and excellent mechanical vector, spreading bacteria in their wake. This is supported by a study done in Palu, Indonesia. Where roaches found in three hospitals were tested for the presence of bacteria. Astiti et al (2018), found that the roaches were harboring the following bacteria. Escherichia coli, Salmonella arizonae, Salmonella sp, Klebsiella ozaenae, Salmonella simultaneous and Salmonella choleraesuis. All of the previously mentioned bacteria were tested and were found to be resistant to amoxicillin. Salmonella choleraesuis, Klebsiella ozaenae, and Escherichia coli were also found to be resistant to chloramphenicol. This is significant because these antibiotics are often the treatment of choice in Palu, Indonesia. This is just another reason to dislike roaches.

Table 1: Shows the 6 types of bacteria present in the roaches found at the hospital.

Original article: Astiti, P. M. A., Bialangi, M., & Kundera, I. N. (2018). Identification of bacteria on Cockroach feet from Hospital area in Palu city and test of sensitivity to antibiotic. IOP Conference Series: Materials Science and Engineering, 434, 012123. doing: 10.1088/1757-899x/434/1/012123

LOOKS LIKE WHOLE FOODS AND TRADER JOES HAVE JUST ADDED A NEW AISLE…BACTERIA SECRETIONS! A NEW TREND? WE HAD A COUPLE QUESTIONS.

By: Alonso Trevino IV

The world of microorganisms has presented the world with many reasons to hate the tiny bacteria and it seems increasingly difficult to avoid them. Still, while we remain skeptical and quite a bit scared about the consequences of our interaction with these organisms of the environment, a new study suggests a completely new twist of fate. While the juicing and healthy meal prep’s frenzy around the world continues to flourish into a full on trend, it seems that our dietetic science friends have begun to find new ways in which to consume the tiny bacteria which we were once afraid of. In a new study that is calling these edible treats, functional foods, “Postbiotics refers to soluble factors (products or metabolic byproducts), secreted by live bacteria, or released after bacterial lysis, such as enzymes, peptides, teichoic acids, peptidoglycan-derived muropeptides, polysaccharides, cell surface proteins, and organic acids” while this concept presents a very controversial reality, it represents a very viable reality nonetheless. This is mainly reassured by the fact that not only do these bacteria excretions create foods with longer shelf lives but they, “may have anti-inflammatory, immunomodulatory, anti-obesogenic, antihypertensive, hypocholesterolemic, anti-proliferative, and antioxidant activities.” (Toala 2018) The presence of these probiotics, prebiotics and postbiotics in popular foods like yogurt have baffled many but more importantly allowed scientists and doctors alike find new ways to incorporate microorganism into functioning human medicines. Will this new use of bacteria allocation be the hipster trend of the 2010’s or will it prove to be a crucial source of health beneficial functioning foods of the future?

Figure 1. In the image above, an abstract view of the essential health benefits of these bacterial friendly foods is depicted.

Original Article:

Aguilar-Toalá, J. E., Garcia-Varela, R., Garcia, H. S., Mata-Haro, V., González-Córdova, A. F., Vallejo-Cordoba, B., & Hernández-Mendoza, A. (2018). Postbiotics: An evolving term within the functional foods field. Trends in Food Science & Technology, 75, 105-114.