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3 years ago

What do u know about earth day?

Biology

2 answers:

7nadin3 [17]3 years ago

8 0

Answer - Well pretty much Earth day is there to help and raise awareness of environmental management and protection to the life on earth like species and such but to also preserve energy and conserve the almost extinct species.

Yes I am talking to you poacher you must stop the hunting on extinct species...

LekaFEV [45]3 years ago

5 0

I learned about it in 5th grade and had too wear green for a week

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A ball is dropped from rest from a high window of a tall building and falls for 4 seconds. Neglecting air resistance, the final

ANTONII [103]

Answer:

-32.9

Explanation:

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3 years ago

Over the past 60 years, the level of carbon dioxide in the atmosphere has been continually increasing. Many scientists hypothesi

padilas [110]

A is the awnser i hope

7 0

4 years ago

Read 2 more answers

DNA binding proteins in prokaryotes regulate gene expression by controlling transcription

kondaur [170]

Answer:

True

Explanation:

Gene expression, which involves the transcription of DNA into mRNA and the subsequent translation of mRNA into proteins, is regulated in the cell of prokaryotes i.e. it is kept under control. This regulatory process, however, is done at the TRANSCRIPTIONAL LEVEL, in prokaryotic organisms like bacteria.

DNA binding proteins called transcription factors bind to the promoter region of a gene and either facilitates/enhance the binding of RNA polymerase or inhibits its binding. The enhancers are called ACTIVATORS while the inhibitors are called REPRESSORS.

6 0

3 years ago

In experimental tests of enzyme evolution, a gene encoding an enzyme was subjected to multiple cycles of random mutagenesis and

ryzh [129]

Answer:

Using directed evolution, we have selected an adipyl acylase enzyme that can be used for a one-step bioconversion of adipyl-7-aminodesacetoxycephalosporanic acid (adipyl-7-ADCA) to 7-ADCA, an important compound for the synthesis of semisynthetic cephalosporins. The starting point for the directed evolution was the glutaryl acylase from Pseudomonas SY-77. The gene fragment encoding the β-subunit was divided into five overlapping parts that were mutagenized separately using error-prone PCR. Mutants were selected in a leucine-deficient host using adipyl-leucine as the sole leucine source. In total, 24 out of 41 plate-selected mutants were found to have a significantly improved ratio of adipyl-7-ADCAversus glutaryl-7-ACA hydrolysis. Several mutations around the substrate-binding site were isolated, especially in two hot spot positions: residues Phe-375 and Asn-266. Five mutants were further characterized by determination of their Michaelis-Menten parameters. Strikingly, mutant SY-77N266H shows a nearly 10-fold improved catalytic efficiency (k cat/K m) on adipyl-7-ADCA, resulting from a 50% increase in k cat and a 6-fold decrease in K m, without decreasing the catalytic efficiency on glutaryl-7-ACA. In contrast, the improved adipyl/glutaryl activity ratio of mutant SY-77F375L mainly is a consequence of a decreased catalytic efficiency toward glutaryl-7-ACA. These results are discussed in the light of a structural model of SY-77 glutaryl acylase.

Semisynthetic cephalosporins and penicillins are the most widely used antibiotics. All clinically important semisynthetic cephalosporins are made from 7-aminocephalosporanic acid (7-ACA)1 or 7-aminodesacetoxycephalosporanic acid (7-ADCA). 7-ACA is derived from cephalosporin C (aminoadipyl-7-ACA), which is obtained by fermentation of the fungus Cephalosporium acremonium. Deacylation is performed either chemically or by a two-step enzymatic process using aD-amino acid oxidase and a glutaryl acylase. The latter enzyme can be found in several Pseudomonas andAcinetobacter species (1-7) as well as in some Gram-positive bacteria (8, 9). 7-ADCA is produced from penicillin G made by Penicillium chrysogenum involving several polluting chemical steps followed by enzymatic deacylation by penicillin acylase (10). A first step toward the introduction of a simplified, more environmentally friendly production of 7-ADCA was the development of a genetically modified P. chrysogenum that produces adipyl-7-ADCA (AD-7-ADCA) (11). For the deacylation of this novel β-lactam, an adipyl acylase is needed. Since the presently identified acylases show little or no activity toward AD-7-ADCA, it is of interest to investigate whether a glutaryl acylase can be converted into an adipyl acylase.

In the past few years, directed evolution has been successfully implemented in changing the substrate specificity of several enzymes (12, 13), resulting in biocatalysts with novel activities. It has become clear that the success of a directed evolution experiment greatly depends on the availability of a good selective substrate, which unfortunately is absent for most bioconversions (12). Artificial substrates that mimic one of the desired catalytic steps may be used for selection; however, it is not clear to what extent the resulting mutants will have lost activity on their natural substrate.

Here we describe a strategy to evolve the glutaryl acylase ofPseudomonas SY-77 into an adipyl acylase with an improved activity toward AD-7-ADCA. The glutaryl acylase fromPseudomonas SY-77 has proven to be particularly suitable for developing an industrial process for deacylation (14). The natural action of the enzyme seems to be directed at hydrolyzing diamino acids with a glutaryl side chain as judged from its high activity on glutaryl-7-A(D)CA. It appears that the enzyme also has a low activity on AD-7-ADCA but no activity on cephalosporin C (2).

Explanation: I know my stuff I get B's in school.

3 0

4 years ago

What are good sources of unsaturated fats?

Marrrta [24]

Answer:

Saturated Fats, Here are 10 high-fat super foods that are actually incredibly healthy and nutritious.

Explanation:

1. Avocados:

Avocados are a fruit, with fat at 77% of calories. They are an excellent source of potassium and fiber, and have been shown to have major benefits for cardiovascular

2. Cheese:

Cheese is incredibly nutritious, and a single slice contains a similar amount of nutrients as a glass of milk. It is a great source of vitamins, minerals, quality proteins and healthy fats.

3. Dark Chocolate:

Dark chocolate is high in fat, but loaded with nutrients and antioxidants. It is very effective at improving cardiovascular health.

4. Whole Eggs:

Whole eggs are among the most nutrient dense foods on the planet. Despite being high in fat and cholesterol, they are incredibly nutritious and healthy.

5. Fatty Fish:

Fatty fish like salmon is loaded with important nutrients, especially omega-3 fatty acids. Eating fatty fish is linked to improved health, and reduced risk of all sorts of diseases.

6. Nuts:

Nuts are loaded with healthy fats, protein, vitamin E and magnesium, and are among the best sources of plant-based protein. Studies show that nuts have many health benefits.

7. Chia Seeds:

Chia seeds are very high in healthy fats, especially an omega-3 fatty acid called ALA. They are also loaded with fiber and minerals, and have numerous health benefits.

8. Extra Virgin Olive Oil:

Extra virgin olive oil has many powerful health benefits, and is incredibly effective at improving cardiovascular health.

9. Coconuts and Coconut Oil:

Coconuts are very high in medium-chain fatty acids, which are metabolized differently than other fats. They can reduce appetite, increase fat burning and provide

10. Full-Fat Yogurt:

Real, full-fat yogurt is incredibly healthy.

It has all the same important nutrients as other high-fat dairy products.

But it’s also loaded with healthy, probiotic bacteria, that can have powerful effects on your health.

Studies show that yogurt can lead to major improvements in digestive health, and may even help fight heart disease and obesity.

Unfortunately, many of the yogurts found on store shelves are low in fat, but loaded with added sugar instead.

It is best to avoid those like the plague.

4 0

3 years ago