All About Bacteria

simplified-bacteria-diagramBacteria are the most fundamental consideration in organic growing. Few people appreciate this fact. As a child we were inoculated with the impression bacteria are our enemies. It wasn't until high school, when a teacher "might" have mentioned that there could be some beneficial "GERMS". Now that I am older and can think for myself, I find that bacterias and other microorganisms could be a friend of mine. Even though you'll undoubtedly find people that are fearful of all microorganisms because of their affiliation with human diseases, numerous microorganisms are important for many valuable functions as well. Some beneficial microbe tasks are commercial fermentation and prescription antibiotics. This is above and beyond the element cycling of nitrogen, carbon, sulfur and others. Live organic technology is all about beneficial microbes. Bacteria are everywhere and in huge numbers. 400,000 could fit on the period at the end of this sentence. Knowing what makes bacteria tick is to know how to grow the best herb plants. Soft fleshy herb plants are bacteria based in contrast to hard woody plants being fungal based. Herb plants symbiont with bacteria in the soil as do woody shrubs with fungi. So heads up!

Bacillus subtilis Biocontrol

Bacillus subtilis Biocontrol

Bacillus subtilis General Description Bacillus subtilis is one of the best understood prokaryotes, in terms of molecular biology and cell biology. Its superb genetic amenability and relatively large size have provided the powerful tools required to investigate a bacterium from all possible aspects. Bacillus subtilis is included in the genus of Gram-positive, rod-shaped (bacillus), bacteria. Bacillus subtilis is an obligate aerobes (oxygen reliant). But more recently, it has been found to have the ability,when in the presence of nitrates or glucose, to be aerobic as well as anaerobic, making it a facultative anaerobes. Bacillus subtilis is an endospore forming bacteria, and the endospore that it forms allows it to withstand extreme temperatures as well as dry environments. Under stressful environmental conditions, the bacteria can produce oval endospores that are not true spores but which the bacteria can reduce themselves to and remain in a dormant state for very long periods. These characteristics originally defined the genus. Bacillus subtilis is not considered pathogenic or toxic and is not a disease causing agent. B. subtilis is readily present everywhere; the air, soil and in plant compost. In this article we are focusing on Basillus subtilis as a soil microorganism. However interestingly enough, it’s main habitat is in our stomachs. Although B subtilis is commonly found in soil, more evidence suggests that it is a normal gut commensal in humans. A 2009 study compared the density of spores found in soil (~106 spores per gram) to that found in human feces (~104 spores per gram). The number of spores found in the human gut is too high to be attributed solely to consumption through food contamination. Soil simply serves as a reservoir, suggesting that B. subtilis inhabits the gut and should be considered as a normal gut commensa.   Bacillus subtilis | Agricultural Tool Basillus subtilis produces an abundance of beneficial toxins and enzymes, most importantly it produces a toxin called subtilisin and a class of lipopeptide antibiotics called iturins.  Iturins has direct fungicidal activity on many pathogens, such as Rhyzoctonia Pythium, Phytophthora, Fusarium, Rhizopus, Mucor, Oidium, Botrytis, Colletotrichum, Erwinia, Pseudomonas, Xanthomonas, as well as nematodos. Iturins help B. subtilis bacteria out-compete other microorganisms by either killing them or reducing their growth rate. In this way subtilis takes up space on the roots, leaving less area or source for occupation by disease pathogens. There is a symbiosis component to the B. subtilis-plant dynamics as well. B subtilis feeds off plant exudates, which also serve as a food source for disease pathogens. Because it consumes exudates, it deprives disease pathogens of a major food source, thereby inhibiting their ability to thrive and reproduce. The exudes feed subtilis and this allows it to protect the plant from pathogens....

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Biofertilizer Aquaponics & Biochar

Biofertilizer Aquaponics  & Biochar

Biofertilizers (also known as “plant-growth promoting rhizobacteria” or PGPR) have come on rapidly in “sustainable” agricultural circles, providing eco-friendly organic agro-input. A biofertilizer contains living microorganisms which, when inoculated into biochar or soil, promotes growth by increasing the supply or availability of major nutrients, such as Nitrogen and Phosphorus. Bio-fertilizers add nutrients through the natural processes of nitrogen fixation, solubilizing phosphorus, and stimulating plant growth through the synthesis of growth-promoting bacterial bio-liquides. Bio-fertilizers do not contain any chemicals. Using Biochar in conjunction with aquaponics is a cutting edge innovation. Biochar has proven to be many times more useful as a medium than rocks. This is true especially when considering applications and/or inoculations with beneficial microorganisms. This is mainly due to the porous structure of Biochar which supports microbial communities. Due to immobilization of phosphate by mineral ions such as Fe, Al and Ca or organic acids, the rate of available phosphate (Pi) is always below plant needs. In addition, chemical Pi fertilizers are also immobilized in the soil, immediately, so that less than 20 percent of added fertilizer is absorbed by plants. Therefore, reduction in Pi resources, on one hand, and environmental pollutions resulting from both production and applications of chemical Pi fertilizer, on the other hand, have already demanded the use of new generation of phosphate fertilizers globally known as phosphate-solubilizing bacteria or phosphate...

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The Amazing Actinomycete Bacteria

The Amazing Actinomycete Bacteria

The Amazing Actinomycete Bacteria Actinomycetes differ from other soil bacteria in many ways. Actinomycetes develop filaments, almost the same as fungal hyphae. Some researchers believe Actinomycetes use these filaments for connecting themselves together with soil pieces. In doing so, they become too big to be eaten by their enemy the protozoan ciliates. Ciliate protozoans engulf and ingest our friends the aerobic bacteria. The most important note concerning Actinomycetes: they are particularly handy at decaying cellulose and chitin. These are two hard, brown carbon compounds in plants, fungus and arthropods, not typical foodstuffs for most other bacteria. Actinomycetes also are tailored to exist in a broader spread of pH compared to other bacteria. If these bacterial acrobatics are not enough to amaze you, here is one that will. Some plants form small pouches devoid of O2, anaerobic nodules, where the Actinomycetes use enzyme nitrogenase to transform nitrogen in the atmosphere to ammonia, NH3+. The image at the top of the page, shows these nodules in the root system of a tree, courtesy of www.toof.org.uk. Image: Actinomycetes |courtesy of...

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Bacteria & The Phyllosphere

Bacteria & The Phyllosphere

Prof. Julia Vorholt, Institute of Microbiology at ETH Zurich “One to ten million unicellular microorganisms live on every square centimeter of stems and foliage making the phyllosphere “the largest biological surface inhabited by microorganisms”, explains Prof. Julia Vorholt at the Institute of Microbiology at ETH Zuric. In recent years new investigative tools from microbiology have made it possible to gain a better insight into microorganisms and their function in complex microbe communities. “Two kinds of bacteria dominate this ecosystem, members of the Methylobacterium genus and unicellular organisms from the Sphingomonas genus. ”, says Vorholt. No matter what plant they studied, microbes from the sphingomonas and methylobacterium genera and their proteins always dominated the scenery. These researchers found over twenty five bacteria genera with more than a hundred species, living on plant leaves. The researchers in Switzerland also discovered previously unknown proteins, “which appear to be important for most bacteria on the leaves of plants”, says Julia Vorholt. What they found was Methylobacteria converting methanol produced by the plants into CO2 for energy. “It is perfectly feasible that the colonization by microbes like methylobacteria or sphingomonas could protect the plants from such attacks…. the bacteria even produce antibiotics to keep the plants healthy”, says Julia Vorholt....

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Bacteria Basics

Bacteria Basics

Bacteria’s Basic Function In spite of their tiny size, bacteria function as the planets second biggest agent for the decomposition of organic material. Fungus is the primary decomposers since they are able to handle tougher, complex ligdin fibers. But without bacteria, the world would be choked in waste materials. Using carbon (carbohydrates) as an energy source, bacteria break down plant materials in an effort to ingest nitrogen and other nutrients. Nutrients will be then kept fixed but “immobilized” within the bacteria’s body. Their consumed nutrients will be discharged and “mineralized” only once the bacteria is eaten or simply dies. What is a Bacteria The term/name bacteria was used for all prokaryotic (no membrane-enclosed nucleus) microbes. However now, there are 2 groups of prokaryotes. Things change as we develop our understanding of life. The size and lack of a nucleus in the new classification, both types possess. But everything else about them is different. The updated classification divides bacteria into these two groups: Bacteria; (also known as Eubacteria) Archaea; (also known as Archaebacteria) The Archaebacteria are very different from the true bacteria. Eubacteria.  These two microbes had a different evolutionary history since life began here on Earth. Archaea bacteria are thought to be the fountain of all higher life forms on the planet. Bacteria The First Life Form The Bacteria evolved some 3 billion years ago. Nature considers them the basic building block of all life. It could be said that all life component parts, including you and me, are made up of bacteria. When more complex living “things” began to evolve, they where composed, like building blocks, of different forms, shapes and parts of bacteria. Before DNA sequencing, bacteria were grouped based on shape alone. The old classification included  coccus (oval), bacillus (rods), and spiral (cork-screw). Now they are classified in 5 major clades: Proteobacteria, Chlamydias, Spirochetes, Gram-positive Bacteria, Cyanobacteria. Classification of Bacteria (Eubacteria) Classification is done by their different traits: shape bacilli: rod-shaped cocci: spherical spirilla: curved walls spore formation or not different ways of energy production… glycolysis for anaerobes, cellular respiration for aerobes Gram stain ( the ability to hold certain dies) The Gram stain is named after Hans Christian Joachim Gram ( 1853-1938) who developed it. cells are stained with a purple dye called crystal violet. preparation is treated with alcohol or acetone. crystal violet washes the stain out of gram-negative cells. To see them now requires the use of a counter-stain of a different color. Bacteria that are not decolorized by the alcohol/acetone wash are gram-positive. Although the Gram stain technique could be viewed as an arbitrary trait for bacterial taxonomy, in fact, it does distinguish between two entirely different types of bacterial cell walls which is a natural division among the bacteria. Of special interest to us is the endophytic bacterium. An endophyte bacteria (or fungus) is an endosymbiont that lives within a plant for at least part of its life without causing apparent disease. Rhyzobium Bacteria and Gluconacetobacter diazotrophicus are two very good examples of beneficial endophytic bacterium. Bacteria Reproduction Bacterias reproduce extremely fast by single cell division. One single bacteria can reproduce itself 5 billion fold in a half day if supplied with sufficient warmth, water, sugars and nutrients. They seldom die-off of old age. Bacterias typically are ingested by another microorganism or wiped out by environmental shifts. Once dead they are eaten by another microorganism, decomposing them to release their nutrients, the most important one being nitrates. Today, bacteria are classified in the kingdom Procaryotae. This term refers to the fact that bacteria consist of prokaryotic cells. This is a class of...

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Bacterial Biofilms

Bacterial Biofilms

Biofilm| Bacterias Natural State When we think of bacteria, beneficial or pathogenic, we imagine a single celled creature swimming independently looking for food. In actuality a bacteria’s natural state is in biofilms, referred to as  plaque or “slime”. The majority of all bacteria on Earth are located in biofim slime, thriving as complex colonies of co-dependent microbes in its self made matrix complete with irrigation and nutrient pathways. Slime or matrix associated microorganisms vastly outnumber organisms in suspension. These surface-bound bacteria behave quite differently from their planktonic counterparts. Planctonic is the word used to describe a free swimming individual bacteria in suspension. I have recently come across a super interesting article in Science Daily. It concerns biofilms forming when individual cells overproduce a polymer that sticks the cells together, allowing the colonization of liquid surfaces. While production of the polymer is metabolically costly to individual cells, the biofilm group benefits from the increased access to oxygen that surface colonization provides. The new findings are reported by Michael Brockhurst of the University of Liverpool. It is a “Must Read” for us all. How Biofilms Move Biofilm bacteria adhere to a self-produced matrix of extracellular polymeric substance, referred to as plaque or “slime”. The slime layer is composed of polysaccharides and proteins. It becomes a matrix where a great variety of waste digesting microbes are found in it’s stratified aerobic and anaerobic settings. Typical organisms include heterotrophic bacteria, nitrifying bacteria nitrosomonas and nitrobactor. The process of surface adhesion and biofilm development is a survival strategy employed by virtually all bacteria and refined over millions of years. This process is designed to anchor microorganisms in a nutritionally advantageous environment and to permit their escape to greener pastures when essential growth factors have been exhausted.  The biofilm protects its inhabitants from predators, dehydration, biocides, and other environmental extremes while regulating population growth and diversity through primitive cell signals. But don’t let your imagination rest there. Image… these creatures express different genes when in a communal setting. They change mode depending on what it’s new purpose is. This supports a higher growth potential, as well as improving efficiency of nutrients reaching desired cells via irrigation type pathways. When fully hydrated, the maytix is predominantly water. In essence, the matrix ia a 3D force field that surrounds, anchors, and protects the bacterial colony. Biofilms | Integral Component In our hydro-tanks as in all of natures settings, biofilms are an integral component of the environment. The report, Global Environmental Change: Microbial Contributions, Microbial Solutions, points out: “. . .the basic chemistry of Earth’s surface is determined by biological activity, especially that of the many trillions of microbes in soil and water. Microbes make up the majority of the living biomass on Earth and, as such, have major roles in the recycling of elements vital to life.” Bacteria are early colonizers of clean surfaces submerged in water.  While some bacteria produce effects that are detrimental to surrounding organisms or hosts, most bacteria are harmless or even beneficial. Aerobic biofilms require water, oxygen and a nutrient food source to maintain cell function. Microbial metabolism causes biodegradation of organic matter and production of metabolic by-products including carbon dioxide (CO2) and deceased micro-organisms. Deceased biofilm components slough off the surface of active biofilm by water turbulence, mechanical sloughing and morph in changing environmental...

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Bacterial Biofilm Water & Ground Treatment

Bacterial Biofilm Water & Ground Treatment

The below article is courtesy of http://biofilmbook.hypertextbookshop.com. It demonstrates two practical uses of a bacterial biofilm. Normally people encounter biofilm (slim) and really don’t know what it is. We all have seen it in it’s worst light. Having a bacterial biofilm on our hydro tanks does pose certain physical problems. It could clog pump lines, for example. But it also has it’s benefits. It is a nitrification dynamo turning organic carbon complexes into simple, soluable nutrients while keeping bacterial pathogens at bay. Water and Wastewater Treatment Engineers have taken advantage of natural biofilm environmental activity in developing water-cleaning systems. Biofilms have been used successfully in water and wastewater treatment for over a century. English engineers developed the first sand filter treatment methods for both water and wastewater treatment in the 1860s. In these filtration systems the surfaces of the filter media act as a support for microbial attachment and growth, resulting in a biofilm adapted to using the organic matter found in that particular water. The end result of biological filtration is a conversion of organic carbon in the water into bacterial biomass. Ideally, this biomass is immobilized on the filter media and removed during the backwash cycle. Drinking water and treated wastewater that have been subjected to microbial activity in a controlled manner in a treatment plant are more “biologically stable” and therefore less likely to contribute to microbial proliferation downstream in distribution system or receiving water. Biologically treated water typically has lower disinfectant demand and disinfection by-product formation potential than conventionally treated water if the source water is high in organic carbon. As drinking water utilities move to using ozone as a primary disinfectant and for taste/odor/color control, biological filters may be necessary to reduce the concentrations of biodegradable organic carbon entering the distribution system. Remediation of contaminated soil and groundwater In soil, biofilm morphology can be highly variable, ranging from patchy discontinuous colonies to thick continuous films, depending on environmental conditions. When toxic organic contaminants (i.e. gasoline, fuel oil, chlorinated solvents) are accidentally released underground, the native soil bacterial population will, to the degree possible, adjust their ecological composition in order to use the organic contaminants as a food source. This process is commonly referred to as “bioremediation” and if successful, potentially has the ability to render initially toxic organic material into harmless by-products. Typical biofilm cell densities found in the vicinity of contaminated ground water sites vary from around 105 to 108 cells per gram of soil. Bioremediation has emerged as a technology of choice for remediating groundwater and soil at many sites contaminated with hazardous wastes. Bioremediation results in 1) the reduction of both contaminant concentration and mass for many subsurface contaminants (e.g., petroleum hydrocarbons, chlorinated organics and nitroaromatics) and/or 2) a beneficial phase transfer or speciation change (e.g., for heavy metals and radionuclides). Subsurface bioremediation is controlled by abiotic geochemical and transport phenomena, including multiphase flow, convective mass transport, adsorption/desorption, and phase partitioning, as well as biotic processes, such as microbial biomass growth and contaminant metabolism. Above article courtesy of...

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Cellulomonas Bacteria

Cellulomonas Bacteria

Research has found that plant photosynthesis produces up to 1.5 1011 tons of dry plant material on earth every year. This huge amount of plant material is primarily composed of plant cell wall polymers of lignin, cellulose, hemicelluloses and pectin. The degradation of these enormous amounts of plant cell wall polymers is carried out by microorganisms, the most important being the aerobic Cellomonas Bacteria. This bacteria uses a series of exudents containing enzymes that are specially effective at breaking down cellulose walls. Cellulomonas fimi was one of the first bacteria to have it’s DNA sequence mapped. It therefore is one of the most researched bacteria. Breaking down cell walls is one of the most important phenomenons in fermentation and bacteria activity. Understanding more would help industries such as pulp and paper. Berkeley Lab tests double-threat microorganisms that can tolerate alkali and break down cellulose The only truly practical bio-fuels will be those made from abundant feedstock like switch-grass, wheat straw, and other woody plants, whose cell walls consist of lignocellulose. After pretreatment to remove or reduce the lignin, the sugary remains of cellulose and hemicellulose are fermented by microorganisms to yield the bio-fuel. “Each additional step in the process adds to the cost,” says Michael Cohen, a visiting professor of biology at the U.S. Department of Energy’s Lawrence Berkeley National Laboratory (Berkeley Lab), increase the efficiency and reduce the cost of bio-fuel processing. “The species of bacteria we’re testing may be able to combine two important steps into one.” Cohen found the unique strain of bacteria, which can tolerate high alkalinity and degrade cellulose at the same time, in a strange and isolated part of California called The Cedars, located inland from Timber Cove in the state’s Outer Coast Range. The site’s deep canyons and rocky serpentine barrens, all but invisible from the area’s few public roads, create a biological island that is home to living things rarely seen elsewhere. Eroding serpentine rock in The Cedars creates highly alkaline springs. Lignin in plant matter that falls into the springs is attacked by the alkalinity, while alkili-tolerant strains of Cellulomonas and other microorganisms break down the cellulose and process the...

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Actinomycetes

Actinomycetes

So just when you thought you knew the difference between a fungus and a bacteria… you learn about actinomycetes bacteria. Actinomycetes Bacteria- is a Cellulomonas Bacteria obtaining its name of fame by being very different from other bacteria. It is actually very fungus like because of its long extending hyphae filaments. It is one of the only bacterias that can break down recalcitrant compounds such as cellulose and chitin as a food source. Therefore this makes it a good component of and beneficial microorganism inoculation community. During the process of composting mainly thermophilic (adapted to high temperatures) and thermotolerant actinomycetes are responsible for decomposition of the organic matter at elevated temperatures. In the initial phase of composting the intensive increase of microbial activity leads to a self heating of the organic material. Actinomycetes, like fungi reproduce via spores. The hyphal growth is followed by fragmentation and release of spores produced...

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Lactobascillus Bacteria

Lactobascillus Bacteria

Lactobascillus Bacteria- is rod-shaped workhorse of decomposing organic plant material into smaller units for plant uptake. Any and all organic growers must have this bacterial superstar at hand for inoculating organic soil if that is the medium for your plants propagation.  It acquired its name because its members convert sugars of lactose into lactic acid. The production of lactic acid makes its surroundings where it id busy breaking down decaying plant parts acidic. This checks the growth of other pathogenic bacteria. Depending on the species they have a lifespan from a half to four hours. They are found everywhere and can be cultured by placing water over rice wash, letting it sit for a week and adding milk. The milk will kill all other bacteria other than Lactobasillus. They are used in the production of yoghurt, cheese, kimchi, chocolate, beer, wine, cider, organic fertilizers and...

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Aerobic And Anaerobic Bacteria

Aerobic And Anaerobic Bacteria

Anaerobic Bacteria The first and most common bacteria would be the anaerobic bacteria, Obligate Anaerobes. They are capable of living in places void of O2 and most will die in the presence of oxygen. Some agile bacteria are Facultative Anaerobes. These are able to live both in and out of an oxygen laden atmosphere but they are rare microbes. Clostridium, for example, is one bacterial genes that does not need oxygen to survive. Everyone’s smelled anaerobic decomposition inside the refrigerator on occasions. So to, we have all smelled the offensive odor of this culprit coming from an old garbage can. Byproducts of their anaerobic decay involve hydrogen sulfide which smells like rotten eggs, butyric acid which smells like vomit, ammonia which will set our nostrils reeling, and vinegar. Anaerobic conditions foster pathogenic bacteria and kill off beneficial aerobic bacteria. . Aerobic Bacteria The second bacteria type and the most important for live organic horticulture, is the aerobic bacteria, or Obligate Aerobes. Though respiration is crucial to life, the precise function that oxygen plays to maintain life is not readily understood. Essentially, in a microorganism that is capable of using it, O2 enables food compounds to be totally digested. This ensures that every possible amount of energy will be  used for maintaining the cell. So the aerobic bacteria have the advantage of metabolic efficiency. Aerobic bacteria can create twenty times more energy, with the equivalent amount of organic compounds, than anaerobic bacteria. What is more, aerobic bacteria aren’t generally known to produce horrible odors. One bacteria in the order of Actinomycetales, genus Streptomyces called actinomycetes, generate enzymes with volatile compounds which gives earth a fresh, clean smell. This is the good quality soil we smell when we instinctively hold a fist full of substrate up to our nose. Interesting how harmonious bacteria agree with us instinctually. Life is good! Good life is king. Thank God....

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Bacteria Foods and Assimilation

Bacteria Foods and Assimilation

Plant root excretions called exudates are one of the three main staples of food for beneficial, symbiotic bacteria. Therefore large colonies are gathered in the rhizosphere, the area surrounding plant roots. In the rhizophere there are additional foods. The plant cell’s root-tip sheds cell parts during its development and growth, which holds nutritional value for the bacteria when decomposed. The third most important food for bacteria is the animal and plant organic compounds that set the bacteria decomposing the larger compounds. This is the dynamo behind the nitrogen and carbon cycle. Food Groups of Bacteria Organic compounds are a composite of long complex molecules. Like beads on a necklace, these complexes are attached end to end. The individual beads are made up of small molecules containing carbon.  Bacteria decompose the carbon complex bonds between each bead along certain points in the chain. So smaller chains are created made up of simple sugars, fats and amino acids. These 3 classes of substances are the fundamental groups of food bacteria will need to support themselves. Bacteria employ digestive enzymes to snap the bonds keeping the beads in the carbon necklace together. This all takes place outside of the bacteria prior to consumption. Many different types of digestive enzymes are produced  and implemented by these microbes. During their 3 billion years of evolution here on Earth, bacteria have adapted so well, they are able to digest organic as well as inorganic materials. What amazes me is that they can so effectively digest all sorts of materials while maintaining the integrity of their own cell walls. Nitrogenous Bacterial Food Different species of bacterias live on different food resources, according to what’s accessible. Nearly all bacteria are happier decomposing fresh vegetative materials, that us composers call “greens”, Nitrogenous Materials. You probably have heard of the Carbon/Nitrogen (C/N) ratio when learning how to create compost. A 20/1 ratio is normally recommended for the balance of tough carbon fibers vs soft nitrogenous material. Bacteria use the carbon for producing energy and the nitrogen for protein production. Composters refer to the carbon (tree leaves and stems) as “browns”, Carbonaceous Material. Before it can be converted into manageable carbon chains for energy, other microbes, normally fungus, need to reduce it. If there is not enough soft, green, nitrogenous materials in the compost mix we end up with little nutrition. Many times we gauge the quality of our compost by the percentage of NPK within. But if their is not enough brown, carbonaceous material in the compost mix, there will not be enough carbohydrates to support the energy level of the microbes at work. Most often it is the dry tree leaves taht provide space and aeration to the compost pile. With little or no air, anaerobic bacteria take over which are pathogenic and harmful to the microbe community, not to mention plants and humans. Bacterial Food Ingestion Bacteria are small and must ingest even smaller pieces of organic matter. So how does a bacteria swallow an elephant? Actually they don’t swallow anything. Bacteria ingest carbohydrates and nutrition right through their cell walls. Their cellular surfaces are made up of proteins that help with this molecular transportation. Within a bacteria’s cell will be a mixture of sugars, proteins, carbons, and charged ions. Molecular transfer through the cellular membrane is actually achieved in a few different ways. Membrane transfer is really an intriguing topic. It is a complex procedure supported by charged electrons found on each side of the tissue layer’s surface. But it is beyond the scope of this article to outline the driving force of osmotic barriers. Yet,...

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