Protoplasmic proteins

For anabolic reactions, which result in the production of new cells, it is important to know the approximate chemical composition of the biomass. The bacterial protoplasm comprises 75 to 80% water. The solid material is composed of several complex organic molecules, such as proteins, carbohydrates, and DNA. The mean composition of these molecules can be approximated by a relatively simple empirical formula, C60H87O23N12P, or in an even more simple form as C5H7O2N10.Numerous other elements such as sulfur, sodium, potassium, calcium, magnesium,... 

Protoplasmic structures are not very stable. Consequently, if protective agents were not employed, destruction of the walls was accompanied by a rapid lysis of the protoplasts, followed by the liberation of most of the cell protein and nucleic acid in soluble form. This could be prevented by employment of the enzyme in a 0.2 M solution of sucrose or cane sugar. After digestion of the cell walls, the living protoplasts rounded up into spheres. 

The biochemical reactions of living cells are controlled by enzymes, which are defined as temperature-sensitive, organic catalysts. Chemically, the enzymes are proteins that are specific in that they will act as catalysts to accelerate specific reactions. Some of these enzymes are associated with the protoplasm of the cell and perform their function within the cell. They are called intracellular enzymes. Other enzymes are excreted by the cell into the surrounding medium and are known as extracellular enzymes. 

It denatures proteins, general protoplasmic poison (but acts slowly). Broad spectrum germicide. 

Almost all physiological processes in plants take place in the presence of water. Essential anabolic reactions (photosynthesis, assimilation, and protein synthesis), and catabolic ones (respiration and hydrolysis) occur in an aqueous cellular environment. Essential elements absorbed by plant roots, and the foods and other metabolites manufactured by the leaves and other tissues, move in aqueous solution from the regions of absorption or manufacture to other parts of the plant where additional anabolic reactions and ultimate food storage take place. Water is the major constituent of protoplasm, and is particularly abundant in young and growing tissues. 

In addition to dioxygen, many other chemical oxidants are used for water and waste treatment purposes. Not surprisingly, they also tend to be powerful microorganism deactivators (and thus good disinfectants) because they may induce abnormal redox processes in cells that kill or deactivate them (or else prevent their reproduction) by the following possible mechanisms attack or alteration of the cell wall, of the cell contents (nucleic acids, protoplasm), or of the cell functions and processes (protein synthesis, redox processes, enzymatic activity). 

Another interesting question relates to the problem of cellular differentiation. The fact that undifferentiated cells contain their contractile protein in a nonstructured form might lead to the speculation that this represents the state of a precursor of the structured actomyosins in the course of cellular development. Actually, this does not seem to be true. Holtzer et al. (1957) working with fluorescent antimyosin antibodies were able to show that, whenever myosin appears in the cellular protoplasm of the chicken embryo myoblasts, it does so already incorporated into a fibrillar structure. 

Under the microscope the immature pollen grain generally consists of two membranes, an outer firmer one called the exospore, which may be variously marked and which possesses deficiencies in the form of pores or clefts, and an inner delicate cellulose membrane called the endospore, which surrounds a protoplasmic interior in which are imbedded a nucleus, oil droplets and frequently starch or protein. 

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