Aminoácidos, proteínas e ácidos nucléicos

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Aminoácidos, proteínas e 
ácidos nucléicos 
Profa Cristina Vicente 
Proteínas 
Figure 2-87 Molecular Biology of the Cell (© Garland Science 2008) 
Sequência de aminoácidos que 
interfere na formação de alfa-
hélices 
 -Sequência repetitiva de Glu (glutamatos), o mesmo 
ocorre com aa básicos 
- Asn, Ser, thr, cys se estiverem em sequência 
- Os aminoácido ácidos ou básicos devem estar 
separados 3 aa, um do outro para permitir a formação 
de um íon-par e a mesma coisa em aa aromáticos o 
que resulta em interação hidrofóbica. 
- Prolinas raramente são encontradas em alfa hélices, 
provocam um dobramento que não permite a 
estabilização 
Figure 3-7a,b,c Molecular Biology of the Cell (© Garland Science 2008) 
Figure 3-7d,e,f Molecular Biology of the Cell (© Garland Science 2008) 
Figure 3-23 Molecular Biology of the Cell (© Garland Science 2008) 
Acidos Nucléicos 
Figure 4-9 Molecular Biology of the Cell (© Garland Science 2008) 
Avery –MacLeod-McCarty 
RNA mensageiro 
Figure 6-21 Molecular Biology of the Cell (© Garland Science 2008) 
Figure 6-21b Molecular Biology of the Cell (© Garland Science 2008) 
Figure 6-27 Molecular Biology of the Cell (© Garland Science 2008) 
RNA transportador 
Figure 6-52a Molecular Biology of the Cell (© Garland Science 2008) 
Figure 6-53 Molecular Biology of the Cell (© Garland Science 2008) 
RNA Ribossômico 
Figure 6-63 Molecular Biology of the Cell (© Garland Science 2008) 
 Principal Types of RNAs Produced in Cells 
TYPE OF RNA FUNCTION 
mRNAs messenger RNAs, code for proteins 
rRNAs ribosomal RNAs, form the basic structure of the ribosome and catalyze 
 protein synthesis 
tRNAs transfer RNAs, central to protein synthesis as adaptors between 
 mRNA and amino acids 
snRNAs small nuclear RNAs, function in a variety of nuclear processes, 
 including the splicing of pre-mRNA 
snoRNAs small nucleolar RNAs, used to process and chemically modify rRNAs 
Other 
noncoding RNAs function in diverse cellular processes, including telomere synthesis, X-
 chromosome inactivation, and the transport of proteins into 
the ER