This is mostly caused by tires that are overinflated. When a tire is overinflated, the tire, in essence, bulges out more in the center. The tire then rides mostly on that bulge and that bulge wears faster than the sides of the tire. Keeping your tires properly inflated can help you to avoid center wear.
Lysozyme is abundant in a number of secretions, such as tears, saliva, human milk, and mucus. It is also present in cytoplasmic granules of the macrophages and the polymorphonuclear neutrophils (PMNs). Large amounts of lysozyme can be found in egg white.
There's a slew of bacteria floating around in your mouth, but it's generally harmless. Since people have different eating habits in different places, you might think an American's saliva might look a lot different from, say, a South African's. Saliva contains more DNA than blood because of all of the oral bacteria. 2  Most common type of bacteria in saliva is Streptococcus, in a mostly harmless form. 3  Saliva spreads molecules to the taste receptors on the tongue.