The phrase "a specific and essential" is correct and usable in written English.
It can be used when emphasizing the importance and particularity of something in a discussion or argument.
Example: "In order to achieve our goals, we need to identify a specific and essential factor that will drive our success."
Alternatives: "a crucial and particular" or "a vital and distinct".
Similarly, loss of ATRX in the 16-cell morula stage has revealed a specific and essential role for ATRX in the formation of the extraembryonic trophoblast in mice.
These findings suggest that the repeat domains within the virulence genes exhibit a specific and essential function, such that natural selection maintains amino acid homology in spite of high levels of nucleotide substitution.
Xeroderma pigmentosum group A (XPA) protein is a specific and essential factor for NER but is not involved in the repair of DSBs [ 41].
The data show that RhoA plays a specific and essential role in pre-T cells because it is required for the expression of transcription factors of the Egr-1 and AP-1 families that have critical functions in thymocyte development.
In a quest to identify the source of microtumors in Ubc9 mutants, we discovered that even though Ubc9 protein is ubiquitously expressed, it plays a specific and essential, niche-independent function in maintaining proliferative quiescence within progenitors of the medullary and transition zones.
Finally, two forms of a disease called multiple mitochondrial dysfunctions syndrome, caused by mutations in either NFU1 or BOLA3, indicate that some Fe-S proteins might acquire their clusters from a specific and essential subset of donor proteins (Cameron et al., 2011; Navarro-Sastre et al., 2011).
Treaties are dead hands, which should be laid upon a country only for specific and essential purposes, and never as a way of governing it.
Contrary to both specific and essential genes, shared genes showed decreased co-expression with their interactors.
ATG5 is required for formation of autophagosomes and is specific and essential for autophagy (Reggiori and Klionsky, 2005).
